diff --git a/modoboa/admin/api/v1/serializers.py b/modoboa/admin/api/v1/serializers.py
index db86de661..545028bdf 100644
--- a/modoboa/admin/api/v1/serializers.py
+++ b/modoboa/admin/api/v1/serializers.py
@@ -6,8 +6,8 @@ from django.conf import settings
 from django.contrib.auth import password_validation
 from django.core.exceptions import ValidationError
 from django.shortcuts import get_object_or_404
-from django.utils.encoding import force_text
-from django.utils.translation import ugettext as _, ugettext_lazy
+from django.utils.encoding import force_str
+from django.utils.translation import gettext as _, gettext_lazy
 
 from drf_spectacular.types import OpenApiTypes
 from drf_spectacular.utils import extend_schema_field
@@ -31,14 +31,14 @@ class DomainSerializer(serializers.ModelSerializer):
 
     quota = serializers.CharField(
         required=False,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Quota shared between mailboxes. Can be expressed in KB, "
             "MB (default) or GB. A value of 0 means no quota."
         )
     )
     default_mailbox_quota = serializers.CharField(
         required=False,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Default quota in MB applied to mailboxes. A value of 0 means "
             "no quota."
         )
@@ -140,7 +140,7 @@ class DomainAliasSerializer(serializers.ModelSerializer):
                 object_type="domain_aliases")
         except lib_exceptions.ModoboaException as inst:
             raise serializers.ValidationError({
-                "domain": force_text(inst)})
+                "domain": force_str(inst)})
         domain_alias.save(creator=creator)
         return domain_alias
 
@@ -331,7 +331,7 @@ class WritableAccountSerializer(AccountSerializer):
                         object_type="mailboxes")
                 except lib_exceptions.ModoboaException as inst:
                     raise serializers.ValidationError({
-                        "mailbox": force_text(inst)})
+                        "mailbox": force_str(inst)})
         condition = (
             not data.get("random_password") and (
                 data.get("password") or
@@ -447,7 +447,7 @@ class AliasSerializer(serializers.ModelSerializer):
     recipients = serializers.ListField(
         child=lib_fields.DRFEmailFieldUTF8AndEmptyUser(),
         allow_empty=False,
-        help_text=ugettext_lazy("A list of recipient")
+        help_text=gettext_lazy("A list of recipient")
     )
 
     class Meta:
diff --git a/modoboa/admin/api/v1/viewsets.py b/modoboa/admin/api/v1/viewsets.py
index 2c60701ed..d417253e7 100644
--- a/modoboa/admin/api/v1/viewsets.py
+++ b/modoboa/admin/api/v1/viewsets.py
@@ -2,7 +2,7 @@
 
 from django import http
 from django.contrib.contenttypes.models import ContentType
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from django_filters import rest_framework as dj_filters
 from drf_spectacular.utils import extend_schema, extend_schema_view
diff --git a/modoboa/admin/api/v2/serializers.py b/modoboa/admin/api/v2/serializers.py
index 9e884bbfe..c4f12b446 100644
--- a/modoboa/admin/api/v2/serializers.py
+++ b/modoboa/admin/api/v2/serializers.py
@@ -8,7 +8,7 @@ from django.conf import settings
 from django.core.exceptions import ValidationError
 from django.core import validators as dj_validators
 from django.shortcuts import get_object_or_404
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from django.contrib.auth import password_validation
 
diff --git a/modoboa/admin/api/v2/tests.py b/modoboa/admin/api/v2/tests.py
index 2bf6a510b..fcea7e95b 100644
--- a/modoboa/admin/api/v2/tests.py
+++ b/modoboa/admin/api/v2/tests.py
@@ -2,7 +2,7 @@
 
 from django.core.files.base import ContentFile
 from django.urls import reverse
-from django.utils.encoding import force_text
+from django.utils.encoding import force_str
 
 from rest_framework.authtoken.models import Token
 
@@ -165,7 +165,7 @@ domainalias; domalias1.com; domain1.com; True
         ]
         self.assertCountEqual(
             expected_response,
-            force_text(response.content.strip()).split("\r\n")
+            force_str(response.content.strip()).split("\r\n")
         )
 
 
@@ -385,7 +385,7 @@ dlist; dlist@test.com; True; user1@test.com; user@extdomain.com
     def test_export(self):
         response = self.client.get(reverse("v2:identities-export"))
         expected_response = "account,admin,,,,True,SuperAdmins,,\r\naccount,admin@test.com,{PLAIN}toto,,,True,DomainAdmins,admin@test.com,10,test.com\r\naccount,admin@test2.com,{PLAIN}toto,,,True,DomainAdmins,admin@test2.com,10,test2.com\r\naccount,user@test.com,{PLAIN}toto,,,True,SimpleUsers,user@test.com,10\r\naccount,user@test2.com,{PLAIN}toto,,,True,SimpleUsers,user@test2.com,10\r\nalias,alias@test.com,True,user@test.com\r\nalias,forward@test.com,True,user@external.com\r\nalias,postmaster@test.com,True,test@truc.fr,toto@titi.com\r\n"  # NOQA:E501
-        received_content = force_text(response.content.strip()).split("\r\n")
+        received_content = force_str(response.content.strip()).split("\r\n")
         # Empty admin password because it is hashed using SHA512-CRYPT
         admin_row = received_content[0].split(",")
         admin_row[2] = ""
diff --git a/modoboa/admin/api/v2/viewsets.py b/modoboa/admin/api/v2/viewsets.py
index 56874a07e..cf473f54a 100644
--- a/modoboa/admin/api/v2/viewsets.py
+++ b/modoboa/admin/api/v2/viewsets.py
@@ -1,6 +1,6 @@
 """Admin API v2 viewsets."""
 
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from django.contrib.contenttypes.models import ContentType
 
diff --git a/modoboa/admin/app_settings.py b/modoboa/admin/app_settings.py
index 5bf9543a2..be18a0ab8 100644
--- a/modoboa/admin/app_settings.py
+++ b/modoboa/admin/app_settings.py
@@ -6,8 +6,8 @@ import os
 
 from django import forms
 from django.conf import settings
-from django.utils.encoding import force_text
-from django.utils.translation import ugettext as _, ugettext_lazy
+from django.utils.encoding import force_str
+from django.utils.translation import gettext as _, gettext_lazy
 from django.forms.fields import GenericIPAddressField
 
 from modoboa.lib.form_utils import SeparatorField, YesNoField
@@ -20,20 +20,20 @@ from . import constants
 class AdminParametersForm(param_forms.AdminParametersForm):
     app = "admin"
 
-    dom_sep = SeparatorField(label=ugettext_lazy("Domains"))
+    dom_sep = SeparatorField(label=gettext_lazy("Domains"))
 
     enable_mx_checks = YesNoField(
-        label=ugettext_lazy("Enable MX checks"),
+        label=gettext_lazy("Enable MX checks"),
         initial=True,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Check that every domain has a valid MX record"
         )
     )
 
     valid_mxs = forms.CharField(
-        label=ugettext_lazy("Valid MXs"),
+        label=gettext_lazy("Valid MXs"),
         initial="",
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "A list of IP or network address every MX record should match."
             " A warning will be sent if a record does not respect it."
         ),
@@ -42,68 +42,68 @@ class AdminParametersForm(param_forms.AdminParametersForm):
     )
 
     domains_must_have_authorized_mx = YesNoField(
-        label=ugettext_lazy("New domains must use authorized MX(s)"),
+        label=gettext_lazy("New domains must use authorized MX(s)"),
         initial=False,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Prevent the creation of a new domain if its MX record does "
             "not use one of the defined addresses."
         )
     )
 
     enable_spf_checks = YesNoField(
-        label=ugettext_lazy("Enable SPF checks"),
+        label=gettext_lazy("Enable SPF checks"),
         initial=True,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Check if every domain has a valid SPF record"
         )
     )
 
     enable_dkim_checks = YesNoField(
-        label=ugettext_lazy("Enable DKIM checks"),
+        label=gettext_lazy("Enable DKIM checks"),
         initial=True,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Check if every domain with DKIM signin enabled has a valid DNS "
             "record"
         )
     )
 
     enable_dmarc_checks = YesNoField(
-        label=ugettext_lazy("Enable DMARC checks"),
+        label=gettext_lazy("Enable DMARC checks"),
         initial=True,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Check if every domain has a valid DMARC record"
         )
     )
 
     enable_autoconfig_checks = YesNoField(
-        label=ugettext_lazy("Enable autoconfig checks"),
+        label=gettext_lazy("Enable autoconfig checks"),
         initial=True,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Check if every domain has a valid records for autoconfiguration"
         )
     )
 
     enable_dnsbl_checks = YesNoField(
-        label=ugettext_lazy("Enable DNSBL checks"),
+        label=gettext_lazy("Enable DNSBL checks"),
         initial=True,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Check every domain against major DNSBL providers"
         )
     )
 
     custom_dns_server = GenericIPAddressField(
-        label=ugettext_lazy("Custom DNS server"),
+        label=gettext_lazy("Custom DNS server"),
         required=False,
         initial="",
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Use a custom DNS server instead of local server configuration"
         )
     )
 
     dkim_keys_storage_dir = forms.CharField(
-        label=ugettext_lazy("DKIM keys storage directory"),
+        label=gettext_lazy("DKIM keys storage directory"),
         initial="",
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Absolute path of the directory where DKIM private keys will "
             "be stored. Make sure this directory belongs to root user "
             "and is not readable by the outside world."
@@ -112,81 +112,81 @@ class AdminParametersForm(param_forms.AdminParametersForm):
     )
 
     dkim_default_key_length = forms.ChoiceField(
-        label=ugettext_lazy("Default DKIM key length"),
+        label=gettext_lazy("Default DKIM key length"),
         initial=2048,
         choices=constants.DKIM_KEY_LENGTHS,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Default length in bits for newly generated DKIM keys."
         )
     )
 
     default_domain_quota = forms.IntegerField(
-        label=ugettext_lazy("Default domain quota"),
+        label=gettext_lazy("Default domain quota"),
         initial=0,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Default quota (in MB) applied to freshly created domains with no "
             "value specified. A value of 0 means no quota."
         )
     )
 
     default_domain_message_limit = forms.IntegerField(
-        label=ugettext_lazy("Default domain sending limit"),
+        label=gettext_lazy("Default domain sending limit"),
         required=False,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Number of messages freshly created domains will be "
             "allowed to send per day. Leave empty for no limit."
         )
     )
 
-    mbsep = SeparatorField(label=ugettext_lazy("Mailboxes"))
+    mbsep = SeparatorField(label=gettext_lazy("Mailboxes"))
 
     handle_mailboxes = YesNoField(
-        label=ugettext_lazy("Handle mailboxes on filesystem"),
+        label=gettext_lazy("Handle mailboxes on filesystem"),
         initial=False,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Rename or remove mailboxes on the filesystem when they get"
             " renamed or removed within Modoboa"
         )
     )
 
     default_mailbox_quota = forms.IntegerField(
-        label=ugettext_lazy("Default mailbox quota"),
+        label=gettext_lazy("Default mailbox quota"),
         initial=0,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Default mailbox quota (in MB) applied to freshly created "
             "mailboxes with no value specified. A value of 0 means no quota."
         )
     )
 
     default_mailbox_message_limit = forms.IntegerField(
-        label=ugettext_lazy("Default mailbox sending limit"),
+        label=gettext_lazy("Default mailbox sending limit"),
         required=False,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Number of messages freshly created mailboxes will be "
             "allowed to send per day. Leave empty for no limit."
         )
     )
 
     auto_account_removal = YesNoField(
-        label=ugettext_lazy("Automatic account removal"),
+        label=gettext_lazy("Automatic account removal"),
         initial=False,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "When a mailbox is removed, also remove the associated account")
     )
 
     auto_create_domain_and_mailbox = YesNoField(
-        label=ugettext_lazy("Automatic domain/mailbox creation"),
+        label=gettext_lazy("Automatic domain/mailbox creation"),
         initial=True,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Create a domain and a mailbox when an account is automatically "
             "created."
         )
     )
 
     create_alias_on_mbox_rename = YesNoField(
-        label=ugettext_lazy("Create an alias when a mailbox is renamed"),
+        label=gettext_lazy("Create an alias when a mailbox is renamed"),
         initial=False,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Create an alias using the old address when a mailbox is renamed."
         )
     )
@@ -207,7 +207,7 @@ class AdminParametersForm(param_forms.AdminParametersForm):
         dpath = None
         code, output = exec_cmd("which dovecot")
         if not code:
-            dpath = force_text(output).strip()
+            dpath = force_str(output).strip()
         else:
             known_paths = getattr(
                 settings, "DOVECOT_LOOKUP_PATH",
@@ -222,7 +222,7 @@ class AdminParametersForm(param_forms.AdminParametersForm):
             except OSError:
                 hide_fields = True
             else:
-                version = force_text(version)
+                version = force_str(version)
                 if code or not version.strip().startswith("2"):
                     hide_fields = True
         else:
@@ -234,7 +234,7 @@ class AdminParametersForm(param_forms.AdminParametersForm):
         """Ensure quota is a positive integer."""
         if self.cleaned_data["default_domain_quota"] < 0:
             raise forms.ValidationError(
-                ugettext_lazy("Must be a positive integer")
+                gettext_lazy("Must be a positive integer")
             )
         return self.cleaned_data["default_domain_quota"]
 
@@ -242,7 +242,7 @@ class AdminParametersForm(param_forms.AdminParametersForm):
         """Ensure quota is a positive integer."""
         if self.cleaned_data["default_mailbox_quota"] < 0:
             raise forms.ValidationError(
-                ugettext_lazy("Must be a positive integer")
+                gettext_lazy("Must be a positive integer")
             )
         return self.cleaned_data["default_mailbox_quota"]
 
@@ -252,12 +252,12 @@ class AdminParametersForm(param_forms.AdminParametersForm):
         if storage_dir:
             if not os.path.isdir(storage_dir):
                 raise forms.ValidationError(
-                    ugettext_lazy("Directory not found.")
+                    gettext_lazy("Directory not found.")
                 )
             code, output = exec_cmd("which openssl")
             if code:
                 raise forms.ValidationError(
-                    ugettext_lazy(
+                    gettext_lazy(
                         "openssl not found, please make sure it is installed.")
                 )
         return storage_dir
@@ -274,7 +274,7 @@ class AdminParametersForm(param_forms.AdminParametersForm):
             ]
         except ValueError:
             raise forms.ValidationError(
-                ugettext_lazy(
+                gettext_lazy(
                     "This field only allows valid IP addresses (or networks)"
                 )
             )
@@ -297,94 +297,94 @@ class AdminParametersForm(param_forms.AdminParametersForm):
 
 GLOBAL_PARAMETERS_STRUCT = collections.OrderedDict([
     ("domains", {
-        "label": ugettext_lazy("Domains"),
+        "label": gettext_lazy("Domains"),
         "params": collections.OrderedDict([
             ("enable_mx_checks", {
-                "label": ugettext_lazy("Enable MX checks"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Enable MX checks"),
+                "help_text": gettext_lazy(
                     "Check that every domain has a valid MX record"
                 )
             }),
             ("valid_mxs", {
-                "label": ugettext_lazy("Valid MXs"),
+                "label": gettext_lazy("Valid MXs"),
                 "display": "enable_mx_checks=true",
-                "help_text": ugettext_lazy(
+                "help_text": gettext_lazy(
                     "A list of IP or network address every MX record should "
                     "match. A warning will be sent if a record does not "
                     "respect it."
                 ),
             }),
             ("domains_must_have_authorized_mx", {
-                "label": ugettext_lazy("New domains must use authorized MX(s)"),
+                "label": gettext_lazy("New domains must use authorized MX(s)"),
                 "display": "enable_mx_checks=true",
-                "help_text": ugettext_lazy(
+                "help_text": gettext_lazy(
                     "Prevent the creation of a new domain if its MX record "
                     "does not use one of the defined addresses."
                 )
             }),
             ("enable_spf_checks", {
-                "label": ugettext_lazy("Enable SPF checks"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Enable SPF checks"),
+                "help_text": gettext_lazy(
                     "Check if every domain has a valid SPF record"
                 )
             }),
             ("enable_dkim_checks", {
-                "label": ugettext_lazy("Enable DKIM checks"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Enable DKIM checks"),
+                "help_text": gettext_lazy(
                     "Check if every domain with DKIM signin enabled "
                     "has a valid DNS record"
                 )
             }),
             ("enable_dmarc_checks", {
-                "label": ugettext_lazy("Enable DMARC checks"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Enable DMARC checks"),
+                "help_text": gettext_lazy(
                     "Check if every domain has a valid DMARC record"
                 )
             }),
             ("enable_autoconfig_checks", {
-                "label": ugettext_lazy("Enable autoconfig checks"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Enable autoconfig checks"),
+                "help_text": gettext_lazy(
                     "Check if every domain has a valid records for "
                     "autoconfiguration"
                 )
             }),
             ("enable_dnsbl_checks", {
-                "label": ugettext_lazy("Enable DNSBL checks"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Enable DNSBL checks"),
+                "help_text": gettext_lazy(
                     "Check every domain against major DNSBL providers"
                 )
             }),
             ("custom_dns_server", {
-                "label": ugettext_lazy("Custom DNS server"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Custom DNS server"),
+                "help_text": gettext_lazy(
                     "Use a custom DNS server instead of local server "
                     "configuration"
                 )
             }),
             ("dkim_keys_storage_dir", {
-                "label": ugettext_lazy("DKIM keys storage directory"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("DKIM keys storage directory"),
+                "help_text": gettext_lazy(
                     "Absolute path of the directory where DKIM private keys "
                     "will be stored. Make sure this directory belongs to root "
                     "user and is not readable by the outside world."
                 ),
             }),
             ("dkim_default_key_length", {
-                "label": ugettext_lazy("Default DKIM key length"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Default DKIM key length"),
+                "help_text": gettext_lazy(
                     "Default length in bits for newly generated DKIM keys."
                 )
             }),
             ("default_domain_quota", {
-                "label": ugettext_lazy("Default domain quota"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Default domain quota"),
+                "help_text": gettext_lazy(
                     "Default quota (in MB) applied to freshly created domains "
                     "with no value specified. A value of 0 means no quota."
                 )
             }),
             ("default_domain_message_limit", {
-                "label": ugettext_lazy("Default domain sending limit"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Default domain sending limit"),
+                "help_text": gettext_lazy(
                     "Number of messages freshly created domains will be "
                     "allowed to send per day. Leave empty for no limit."
                 )
@@ -392,47 +392,47 @@ GLOBAL_PARAMETERS_STRUCT = collections.OrderedDict([
         ])
     }),
     ("mailboxes", {
-        "label": ugettext_lazy("Mailboxes"),
+        "label": gettext_lazy("Mailboxes"),
         "params": collections.OrderedDict([
             ("handle_mailboxes", {
-                "label": ugettext_lazy("Handle mailboxes on filesystem"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Handle mailboxes on filesystem"),
+                "help_text": gettext_lazy(
                     "Rename or remove mailboxes on the filesystem when they get"
                     " renamed or removed within Modoboa"
                 )
             }),
             ("default_mailbox_quota", {
-                "label": ugettext_lazy("Default mailbox quota"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Default mailbox quota"),
+                "help_text": gettext_lazy(
                     "Default mailbox quota (in MB) applied to freshly created "
                     "domains with no value specified. A value of 0 means no "
                     "quota."
                 )
             }),
             ("default_mailbox_message_limit", {
-                "label": ugettext_lazy("Default mailbox sending limit"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Default mailbox sending limit"),
+                "help_text": gettext_lazy(
                     "Number of messages freshly created mailboxes will be "
                     "allowed to send per day. Leave empty for no limit."
                 )
             }),
             ("auto_account_removal", {
-                "label": ugettext_lazy("Automatic account removal"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Automatic account removal"),
+                "help_text": gettext_lazy(
                     "When a mailbox is removed, also remove the associated "
                     "account")
             }),
             ("auto_create_domain_and_mailbox", {
-                "label": ugettext_lazy("Automatic domain/mailbox creation"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Automatic domain/mailbox creation"),
+                "help_text": gettext_lazy(
                     "Create a domain and a mailbox when an account is "
                     "automatically created."
                 )
             }),
             ("create_alias_on_mbox_rename", {
-                "label": ugettext_lazy(
+                "label": gettext_lazy(
                     "Create an alias when a mailbox is renamed"),
-                "help_text": ugettext_lazy(
+                "help_text": gettext_lazy(
                     "Create an alias using the old address when a mailbox is "
                     "renamed."
                 )
@@ -448,8 +448,8 @@ def load_admin_settings():
     from .api.v2 import serializers
 
     param_tools.registry.add(
-        "global", AdminParametersForm, ugettext_lazy("Administration"))
+        "global", AdminParametersForm, gettext_lazy("Administration"))
     param_tools.registry.add2(
-        "global", "admin", ugettext_lazy("Administration"),
+        "global", "admin", gettext_lazy("Administration"),
         GLOBAL_PARAMETERS_STRUCT,
         serializers.AdminGlobalParametersSerializer)
diff --git a/modoboa/admin/constants.py b/modoboa/admin/constants.py
index c1272c052..56924eef3 100644
--- a/modoboa/admin/constants.py
+++ b/modoboa/admin/constants.py
@@ -1,6 +1,6 @@
 """Admin constants."""
 
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import gettext_lazy as _
 
 DNSBL_PROVIDERS = [
     "b.barracudacentral.org",
diff --git a/modoboa/admin/forms/account.py b/modoboa/admin/forms/account.py
index e406c147b..fac6c1e32 100644
--- a/modoboa/admin/forms/account.py
+++ b/modoboa/admin/forms/account.py
@@ -8,7 +8,7 @@ from django.conf import settings
 from django.contrib.auth import password_validation
 from django.http import QueryDict
 from django.urls import reverse
-from django.utils.translation import ugettext as _, ugettext_lazy
+from django.utils.translation import gettext as _, gettext_lazy
 
 from modoboa.core import signals as core_signals
 from modoboa.core.models import User
@@ -29,34 +29,34 @@ class AccountFormGeneral(forms.ModelForm):
     """General account form."""
 
     username = forms.CharField(
-        label=ugettext_lazy("Username"),
-        help_text=ugettext_lazy(
+        label=gettext_lazy("Username"),
+        help_text=gettext_lazy(
             "The user's name. Must be a valid e-mail address for simple users "
             "or administrators with a mailbox."
         )
     )
     role = forms.ChoiceField(
-        label=ugettext_lazy("Role"),
-        choices=[("", ugettext_lazy("Choose"))],
-        help_text=ugettext_lazy("What level of permission this user will have")
+        label=gettext_lazy("Role"),
+        choices=[("", gettext_lazy("Choose"))],
+        help_text=gettext_lazy("What level of permission this user will have")
     )
     random_password = forms.BooleanField(
-        label=ugettext_lazy("Random password"),
-        help_text=ugettext_lazy(
+        label=gettext_lazy("Random password"),
+        help_text=gettext_lazy(
             "Generate a random password. If you're updating this account and "
             "check this box, a new password will be generated."
         ),
         required=False
     )
     password1 = forms.CharField(
-        label=ugettext_lazy("Password"), widget=forms.widgets.PasswordInput,
+        label=gettext_lazy("Password"), widget=forms.widgets.PasswordInput,
         required=False
     )
 
     password2 = forms.CharField(
-        label=ugettext_lazy("Confirmation"),
+        label=gettext_lazy("Confirmation"),
         widget=forms.widgets.PasswordInput,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Enter the same password as above, for verification."
         ),
         required=False
@@ -69,7 +69,7 @@ class AccountFormGeneral(forms.ModelForm):
             "master_user",
         )
         labels = {
-            "is_active": ugettext_lazy("Enabled")
+            "is_active": gettext_lazy("Enabled")
         }
 
     def __init__(self, user, *args, **kwargs):
@@ -223,14 +223,14 @@ class AccountFormMail(forms.Form, DynamicForm):
     """Form to handle mail part."""
 
     email = lib_fields.UTF8EmailField(
-        label=ugettext_lazy("E-mail"), required=False)
+        label=gettext_lazy("E-mail"), required=False)
     create_alias_with_old_address = forms.BooleanField(
-        label=ugettext_lazy("Create an alias using the old address"),
+        label=gettext_lazy("Create an alias using the old address"),
         required=False,
         initial=False
     )
     quota = forms.CharField(
-        label=ugettext_lazy("Quota"),
+        label=gettext_lazy("Quota"),
         required=False,
         help_text=_(
             "Quota for this mailbox, can be expressed in KB, MB (default) or "
@@ -243,25 +243,25 @@ class AccountFormMail(forms.Form, DynamicForm):
     )
     quota_act = forms.BooleanField(required=False)
     message_limit = forms.IntegerField(
-        label=ugettext_lazy("Message sending limit"),
+        label=gettext_lazy("Message sending limit"),
         required=False,
         min_value=0,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Number of messages this mailbox can send per day")
     )
     aliases = lib_fields.UTF8AndEmptyUserEmailField(
-        label=ugettext_lazy("Alias(es)"),
+        label=gettext_lazy("Alias(es)"),
         required=False,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Alias(es) of this mailbox. Indicate only one address per input, "
             "press ENTER to add a new input. To create a catchall alias, just "
             "enter the domain name (@domain.tld)."
         )
     )
     senderaddress = lib_fields.UTF8AndEmptyUserEmailField(
-        label=ugettext_lazy("Sender addresses"),
+        label=gettext_lazy("Sender addresses"),
         required=False,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Additional sender address(es) for this account. The user will be "
             "allowed to send emails using this address, even if it "
             "does not exist locally. Indicate one address per input. Press "
@@ -473,9 +473,9 @@ class AccountPermissionsForm(forms.Form, DynamicForm):
     """A form to assign domain(s) permission."""
 
     domains = lib_fields.DomainNameField(
-        label=ugettext_lazy("Domain(s)"),
+        label=gettext_lazy("Domain(s)"),
         required=False,
-        help_text=ugettext_lazy("Domain(s) that user administrates")
+        help_text=gettext_lazy("Domain(s) that user administrates")
     )
 
     def __init__(self, *args, **kwargs):
diff --git a/modoboa/admin/forms/alias.py b/modoboa/admin/forms/alias.py
index 3a5238ac6..86e95b5da 100644
--- a/modoboa/admin/forms/alias.py
+++ b/modoboa/admin/forms/alias.py
@@ -4,7 +4,7 @@ from collections import OrderedDict
 
 from django import forms
 from django.http import QueryDict
-from django.utils.translation import ugettext as _, ugettext_lazy
+from django.utils.translation import gettext as _, gettext_lazy
 
 from modoboa.core import signals as core_signals
 from modoboa.lib import exceptions as lib_exceptions, fields as lib_fields
@@ -17,19 +17,19 @@ class AliasForm(forms.ModelForm, DynamicForm):
     """A form to create/modify an alias."""
 
     random_address = forms.BooleanField(
-        label=ugettext_lazy("Random address"),
+        label=gettext_lazy("Random address"),
         required=False)
     address = lib_fields.UTF8AndEmptyUserEmailField(
-        label=ugettext_lazy("Email address"),
-        help_text=ugettext_lazy(
+        label=gettext_lazy("Email address"),
+        help_text=gettext_lazy(
             "The alias address. To create a catchall alias, just enter the "
             "domain name (@domain.tld)."
         ),
         widget=forms.TextInput(attrs={"class": "form-control"})
     )
     recipients = lib_fields.UTF8AndEmptyUserEmailField(
-        label=ugettext_lazy("Recipients"), required=False,
-        help_text=ugettext_lazy(
+        label=gettext_lazy("Recipients"), required=False,
+        help_text=gettext_lazy(
             "Addresses this alias will point to. Indicate only one address "
             "per input, press ENTER to add a new input."
         ),
@@ -40,7 +40,7 @@ class AliasForm(forms.ModelForm, DynamicForm):
         model = Alias
         fields = ("address", "domain", "enabled", "expire_at", "description")
         labels = {
-            "domain": ugettext_lazy("Domain")
+            "domain": gettext_lazy("Domain")
         }
         widgets = {
             "domain": forms.widgets.Select(
diff --git a/modoboa/admin/forms/domain.py b/modoboa/admin/forms/domain.py
index ac915608d..01375d217 100644
--- a/modoboa/admin/forms/domain.py
+++ b/modoboa/admin/forms/domain.py
@@ -5,8 +5,8 @@ from functools import reduce
 from django import forms
 from django.http import QueryDict
 from django.urls import reverse
-from django.utils.encoding import force_text
-from django.utils.translation import ugettext as _, ugettext_lazy
+from django.utils.encoding import force_str
+from django.utils.translation import gettext as _, gettext_lazy
 
 from modoboa.core import signals as core_signals
 from modoboa.core.models import User
@@ -25,30 +25,30 @@ class DomainFormGeneral(forms.ModelForm, DynamicForm):
     """A form to create/edit a domain."""
 
     type = forms.ChoiceField(  # NOQA:A003
-        label=ugettext_lazy("Type"),
+        label=gettext_lazy("Type"),
     )
     aliases = DomainNameField(
-        label=ugettext_lazy("Alias(es)"),
+        label=gettext_lazy("Alias(es)"),
         required=False,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Alias(es) of this domain. Indicate only one name per input, "
             "press ENTER to add a new input."
         )
     )
     dkim_key_selector = forms.CharField(
-        label=ugettext_lazy("Key selector"), initial="modoboa", required=False)
+        label=gettext_lazy("Key selector"), initial="modoboa", required=False)
     quota = forms.CharField(
-        label=ugettext_lazy("Quota"),
+        label=gettext_lazy("Quota"),
         initial=0,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Quota shared between mailboxes. Can be expressed in KB, "
             "MB (default) or GB. A value of 0 means no quota."
         )
     )
     default_mailbox_quota = forms.CharField(
-        label=ugettext_lazy("Default mailbox quota"),
+        label=gettext_lazy("Default mailbox quota"),
         initial=0,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Default quota applied to mailboxes. Can be expressed in KB, MB "
             "(default) or GB. A value of 0 means no quota."
         )
@@ -97,7 +97,7 @@ class DomainFormGeneral(forms.ModelForm, DynamicForm):
             name, [(DomainAlias, _("domain alias"))])
         if label is not None:
             raise forms.ValidationError(
-                _("A %s with this name already exists") % force_text(label))
+                _("A %s with this name already exists") % force_str(label))
 
         domains_must_have_authorized_mx = (
             param_tools.get_global_parameter("domains_must_have_authorized_mx")
@@ -182,7 +182,7 @@ class DomainFormGeneral(forms.ModelForm, DynamicForm):
             if label is not None:
                 self.add_error(
                     k, _("A %s with this name already exists")
-                    % force_text(label)
+                    % force_str(label)
                 )
             else:
                 self.aliases.append(cleaned_data[k])
@@ -227,17 +227,17 @@ class DomainFormOptions(forms.Form):
     """A form containing options for domain creation."""
 
     create_dom_admin = YesNoField(
-        label=ugettext_lazy("Create a domain administrator"),
+        label=gettext_lazy("Create a domain administrator"),
         initial=False,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Automatically create an administrator for this domain"
         )
     )
 
     dom_admin_username = forms.CharField(
-        label=ugettext_lazy("Name"),
+        label=gettext_lazy("Name"),
         initial="admin",
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "The administrator's name. Don't include the domain's name here, "
             "it will be automatically appended."
         ),
@@ -245,27 +245,27 @@ class DomainFormOptions(forms.Form):
     )
 
     random_password = YesNoField(
-        label=ugettext_lazy("Random password"),
+        label=gettext_lazy("Random password"),
         initial=False,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Generate a random password for the administrator."
         ),
         required=False
     )
 
     with_mailbox = YesNoField(
-        label=ugettext_lazy("With a mailbox"),
+        label=gettext_lazy("With a mailbox"),
         initial=True,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Create a mailbox for the administrator."
         ),
         required=False
     )
 
     create_aliases = YesNoField(
-        label=ugettext_lazy("Create aliases"),
+        label=gettext_lazy("Create aliases"),
         initial=True,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Automatically create standard aliases for this domain"
         ),
         required=False
diff --git a/modoboa/admin/forms/export.py b/modoboa/admin/forms/export.py
index 234bbd9d4..786a726e4 100644
--- a/modoboa/admin/forms/export.py
+++ b/modoboa/admin/forms/export.py
@@ -1,12 +1,12 @@
 """Export related forms."""
 
 from django import forms
-from django.utils.translation import ugettext_lazy
+from django.utils.translation import gettext_lazy
 
 
 class ExportDataForm(forms.Form):
     sepchar = forms.CharField(
-        label=ugettext_lazy("Separator"),
+        label=gettext_lazy("Separator"),
         max_length=1,
         required=False,
         widget=forms.TextInput(attrs={"class": "form-control"})
diff --git a/modoboa/admin/forms/forward.py b/modoboa/admin/forms/forward.py
index 5cd7b1b7c..8308d2f2a 100644
--- a/modoboa/admin/forms/forward.py
+++ b/modoboa/admin/forms/forward.py
@@ -2,23 +2,23 @@
 
 from django import forms
 from django.core import validators
-from django.utils.translation import ugettext_lazy
+from django.utils.translation import gettext_lazy
 
 
 class ForwardForm(forms.Form):
     """Forward definition form."""
 
     dest = forms.CharField(
-        label=ugettext_lazy("Recipient(s)"),
+        label=gettext_lazy("Recipient(s)"),
         widget=forms.Textarea(attrs={"class": "form-control"}),
         required=False,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Indicate one or more recipients separated by a ','")
     )
     keepcopies = forms.BooleanField(
-        label=ugettext_lazy("Keep local copies"),
+        label=gettext_lazy("Keep local copies"),
         required=False,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Forward messages and store copies into your local mailbox")
     )
 
diff --git a/modoboa/admin/forms/import_.py b/modoboa/admin/forms/import_.py
index e598658e7..acdb1f3fb 100644
--- a/modoboa/admin/forms/import_.py
+++ b/modoboa/admin/forms/import_.py
@@ -1,23 +1,23 @@
 """Forms related to import operations."""
 
 from django import forms
-from django.utils.translation import ugettext_lazy
+from django.utils.translation import gettext_lazy
 
 
 class ImportDataForm(forms.Form):
 
     """Base form to import objects."""
 
-    sourcefile = forms.FileField(label=ugettext_lazy("Select a file"))
+    sourcefile = forms.FileField(label=gettext_lazy("Select a file"))
     sepchar = forms.CharField(
-        label=ugettext_lazy("Separator"),
+        label=gettext_lazy("Separator"),
         max_length=1,
         required=False,
         widget=forms.TextInput(attrs={"class": "form-control"})
     )
     continue_if_exists = forms.BooleanField(
-        label=ugettext_lazy("Continue on error"), required=False,
-        help_text=ugettext_lazy("Don't treat duplicated objects as error")
+        label=gettext_lazy("Continue on error"), required=False,
+        help_text=gettext_lazy("Don't treat duplicated objects as error")
     )
 
     def __init__(self, *args, **kwargs):
@@ -35,8 +35,8 @@ class ImportIdentitiesForm(ImportDataForm):
     """A form to import identities."""
 
     crypt_password = forms.BooleanField(
-        label=ugettext_lazy("Crypt passwords"), required=False,
-        help_text=ugettext_lazy(
+        label=gettext_lazy("Crypt passwords"), required=False,
+        help_text=gettext_lazy(
             "Check this option if passwords contained in your file "
             "are not crypted"
         )
diff --git a/modoboa/admin/handlers.py b/modoboa/admin/handlers.py
index 0b3bef1ab..d7bfc1361 100644
--- a/modoboa/admin/handlers.py
+++ b/modoboa/admin/handlers.py
@@ -4,7 +4,7 @@ from django.contrib.contenttypes.models import ContentType
 from django.db.models import signals
 from django.dispatch import receiver
 from django.urls import reverse
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from modoboa.core import models as core_models, signals as core_signals
 from modoboa.lib import exceptions, permissions, signals as lib_signals
diff --git a/modoboa/admin/lib.py b/modoboa/admin/lib.py
index 80fbaee0a..e88f55b45 100644
--- a/modoboa/admin/lib.py
+++ b/modoboa/admin/lib.py
@@ -15,8 +15,8 @@ from dns.name import IDNA_2008_UTS_46
 from django.core.exceptions import ValidationError
 from django.db import transaction
 from django.db.models import Q
-from django.utils.encoding import smart_text
-from django.utils.translation import ugettext as _
+from django.utils.encoding import smart_str
+from django.utils.translation import gettext as _
 
 from django.contrib.auth import password_validation
 from django.contrib.contenttypes.models import ContentType
@@ -232,14 +232,14 @@ def get_domain_mx_list(domain):
                 continue
             for ip_answer in ip_answers:
                 try:
-                    address_smart = smart_text(ip_answer.address)
+                    address_smart = smart_str(ip_answer.address)
                     mx_ip = ipaddress.ip_address(address_smart)
                 except ValueError as e:
                     logger.warning(
                         _("Invalid IP address format for "
                           "{domain}; {addr}").format(
                               domain=mx_domain,
-                            addr=smart_text(ip_answer.address)
+                            addr=smart_str(ip_answer.address)
                           ), exc_info=e)
                 else:
                     result.append((mx_domain, mx_ip))
@@ -249,7 +249,7 @@ def get_domain_mx_list(domain):
 def domain_has_authorized_mx(name):
     """Check if domain has authorized mx record at least."""
     valid_mxs = param_tools.get_global_parameter("valid_mxs")
-    valid_mxs = [ipaddress.ip_network(smart_text(v.strip()))
+    valid_mxs = [ipaddress.ip_network(smart_str(v.strip()))
                  for v in valid_mxs.split() if v.strip()]
     domain_mxs = get_domain_mx_list(name)
     for _mx_addr, mx_ip_addr in domain_mxs:
diff --git a/modoboa/admin/management/commands/subcommands/_export.py b/modoboa/admin/management/commands/subcommands/_export.py
index 050eda391..694035adb 100644
--- a/modoboa/admin/management/commands/subcommands/_export.py
+++ b/modoboa/admin/management/commands/subcommands/_export.py
@@ -3,7 +3,7 @@
 import csv
 
 from django.core.management.base import BaseCommand
-from django.utils.encoding import smart_text
+from django.utils.encoding import smart_str
 
 from modoboa.core.extensions import exts_pool
 from modoboa.core.models import User
@@ -56,5 +56,5 @@ class ExportCommand(BaseCommand):
     def handle(self, *args, **options):
         exts_pool.load_all()
         self.csvwriter = csv.writer(
-            self.stdout, delimiter=smart_text(options["sepchar"]))
+            self.stdout, delimiter=smart_str(options["sepchar"]))
         getattr(self, "export_{}".format(options["objtype"]))()
diff --git a/modoboa/admin/management/commands/subcommands/_import.py b/modoboa/admin/management/commands/subcommands/_import.py
index d4b7054db..8e3562a97 100644
--- a/modoboa/admin/management/commands/subcommands/_import.py
+++ b/modoboa/admin/management/commands/subcommands/_import.py
@@ -9,7 +9,7 @@ from chardet.universaldetector import UniversalDetector
 
 from django.core.management.base import BaseCommand, CommandError
 from django.db import transaction
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from modoboa.core import models as core_models
 from modoboa.core.extensions import exts_pool
diff --git a/modoboa/admin/management/commands/subcommands/_manage_dkim_keys.py b/modoboa/admin/management/commands/subcommands/_manage_dkim_keys.py
index 1d125ed43..d3ccdda67 100644
--- a/modoboa/admin/management/commands/subcommands/_manage_dkim_keys.py
+++ b/modoboa/admin/management/commands/subcommands/_manage_dkim_keys.py
@@ -3,8 +3,8 @@
 import os
 
 from django.core.management.base import BaseCommand
-from django.utils.encoding import smart_text
-from django.utils.translation import ugettext as _
+from django.utils.encoding import smart_str
+from django.utils.translation import gettext as _
 
 from modoboa.lib import sysutils
 from modoboa.parameters import tools as param_tools
@@ -41,15 +41,15 @@ class ManageDKIMKeys(BaseCommand):
             "openssl genrsa -out {} {}".format(pkey_path, key_size))
         if code:
             print("Failed to generate DKIM private key for domain {}: {}"
-                  .format(domain.name, smart_text(output)))
+                  .format(domain.name, smart_str(output)))
         domain.dkim_private_key_path = pkey_path
         code, output = sysutils.exec_cmd(
             "openssl rsa -in {} -pubout".format(pkey_path))
         if code:
             print("Failed to generate DKIM public key for domain {}: {}"
-                  .format(domain.name, smart_text(output)))
+                  .format(domain.name, smart_str(output)))
         public_key = ""
-        for cpt, line in enumerate(smart_text(output).splitlines()):
+        for cpt, line in enumerate(smart_str(output).splitlines()):
             if cpt == 0 or line.startswith("-----"):
                 continue
             public_key += line
diff --git a/modoboa/admin/management/commands/subcommands/_mx.py b/modoboa/admin/management/commands/subcommands/_mx.py
index d1ea6abee..41fd9a349 100644
--- a/modoboa/admin/management/commands/subcommands/_mx.py
+++ b/modoboa/admin/management/commands/subcommands/_mx.py
@@ -10,9 +10,9 @@ from django.core.mail import EmailMessage
 from django.core.management.base import BaseCommand
 from django.template.loader import render_to_string
 from django.utils import timezone
-from django.utils.encoding import smart_text
+from django.utils.encoding import smart_str
 from django.utils.functional import cached_property
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from modoboa.admin import constants, models
 from modoboa.dnstools import models as dns_models
@@ -40,7 +40,7 @@ class CheckMXRecords(BaseCommand):
     def valid_mxs(self):
         """Return valid MXs set in admin."""
         valid_mxs = param_tools.get_global_parameter("valid_mxs")
-        return [ipaddress.ip_network(smart_text(v.strip()))
+        return [ipaddress.ip_network(smart_str(v.strip()))
                 for v in valid_mxs.split() if v.strip()]
 
     def add_arguments(self, parser):
@@ -70,7 +70,7 @@ class CheckMXRecords(BaseCommand):
         results = {}
         for ip, mxs in mx_list.items():
             try:
-                ip = ipaddress.ip_address(smart_text(ip))
+                ip = ipaddress.ip_address(smart_str(ip))
             except ValueError:
                 continue
             else:
diff --git a/modoboa/admin/models/alias.py b/modoboa/admin/models/alias.py
index b24b89de5..312f52020 100644
--- a/modoboa/admin/models/alias.py
+++ b/modoboa/admin/models/alias.py
@@ -7,9 +7,9 @@ from django.core.exceptions import ValidationError
 from django.db import models
 from django.urls import reverse
 from django.utils.encoding import (
-    force_bytes, force_str, smart_text
+    force_bytes, force_str, smart_str
 )
-from django.utils.translation import ugettext as _, ugettext_lazy
+from django.utils.translation import gettext as _, gettext_lazy
 
 from reversion import revisions as reversion
 
@@ -68,22 +68,22 @@ class Alias(AdminObject):
     """Mailbox alias."""
 
     address = models.CharField(
-        ugettext_lazy("address"), max_length=254,
-        help_text=ugettext_lazy(
+        gettext_lazy("address"), max_length=254,
+        help_text=gettext_lazy(
             "The alias address."
         )
     )
     domain = models.ForeignKey(Domain, null=True, on_delete=models.CASCADE)
     enabled = models.BooleanField(
-        ugettext_lazy("enabled"),
-        help_text=ugettext_lazy("Check to activate this alias"),
+        gettext_lazy("enabled"),
+        help_text=gettext_lazy("Check to activate this alias"),
         default=True
     )
     internal = models.BooleanField(default=False)
     description = models.TextField(
-        ugettext_lazy("Description"), blank=True)
+        gettext_lazy("Description"), blank=True)
     expire_at = models.DateTimeField(
-        ugettext_lazy("Expire at"), blank=True, null=True)
+        gettext_lazy("Expire at"), blank=True, null=True)
     _objectname = "MailboxAlias"
 
     objects = AliasManager()
@@ -258,6 +258,6 @@ class AliasRecipient(models.Model):
 
     def __str__(self):
         """Return alias and recipient."""
-        return smart_text(
+        return smart_str(
             "{} -> {}".format(self.alias.address, self.address)
         )
diff --git a/modoboa/admin/models/domain.py b/modoboa/admin/models/domain.py
index 8b8fc0a1b..dd997b9a6 100644
--- a/modoboa/admin/models/domain.py
+++ b/modoboa/admin/models/domain.py
@@ -6,9 +6,9 @@ from reversion import revisions as reversion
 
 from django.db import models
 from django.utils import timezone
-from django.utils.encoding import force_text, smart_text
+from django.utils.encoding import force_str, smart_str
 from django.utils.functional import cached_property
-from django.utils.translation import ugettext as _, ugettext_lazy
+from django.utils.translation import gettext as _, gettext_lazy
 
 from modoboa.core import signals as core_signals
 from modoboa.core.models import User
@@ -23,46 +23,46 @@ from . import mixins
 class Domain(mixins.MessageLimitMixin, AdminObject):
     """Mail domain."""
 
-    name = models.CharField(ugettext_lazy("name"), max_length=253, unique=True,
-                            help_text=ugettext_lazy("The domain name"))
+    name = models.CharField(gettext_lazy("name"), max_length=253, unique=True,
+                            help_text=gettext_lazy("The domain name"))
     quota = models.PositiveIntegerField(
         default=0,
     )
     default_mailbox_quota = models.PositiveIntegerField(
-        verbose_name=ugettext_lazy("Default mailbox quota"),
+        verbose_name=gettext_lazy("Default mailbox quota"),
         default=0
     )
     message_limit = models.PositiveIntegerField(
-        ugettext_lazy("Message sending limit"),
+        gettext_lazy("Message sending limit"),
         null=True, blank=True,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Number of messages this domain can send per day"
         )
     )
     enabled = models.BooleanField(
-        ugettext_lazy("enabled"),
-        help_text=ugettext_lazy("Check to activate this domain"),
+        gettext_lazy("enabled"),
+        help_text=gettext_lazy("Check to activate this domain"),
         default=True
     )
     type = models.CharField(default="domain", max_length=20)  # NOQA:A003
     enable_dns_checks = models.BooleanField(
-        ugettext_lazy("Enable DNS checks"), default=True,
-        help_text=ugettext_lazy("Check to enable DNS checks for this domain")
+        gettext_lazy("Enable DNS checks"), default=True,
+        help_text=gettext_lazy("Check to enable DNS checks for this domain")
     )
 
     transport = models.OneToOneField(
         "transport.Transport", null=True, on_delete=models.SET_NULL)
 
     enable_dkim = models.BooleanField(
-        ugettext_lazy("Enable DKIM signing"),
-        help_text=ugettext_lazy(
+        gettext_lazy("Enable DKIM signing"),
+        help_text=gettext_lazy(
             "If you activate this feature, a DKIM key will be "
             "generated for this domain."),
         default=False
     )
     dkim_key_selector = models.CharField(max_length=30, default="modoboa")
     dkim_key_length = models.PositiveIntegerField(
-        ugettext_lazy("Key length"), choices=constants.DKIM_KEY_LENGTHS,
+        gettext_lazy("Key length"), choices=constants.DKIM_KEY_LENGTHS,
         blank=True, null=True
     )
     dkim_public_key = models.TextField(blank=True)
@@ -339,7 +339,7 @@ class Domain(mixins.MessageLimitMixin, AdminObject):
         super().delete()
 
     def __str__(self):
-        return smart_text(self.name)
+        return smart_str(self.name)
 
     def from_csv(self, user, row):
         """Create a new domain from a CSV entry.
@@ -397,7 +397,7 @@ class Domain(mixins.MessageLimitMixin, AdminObject):
         result = [
             [
                 "domain",
-                force_text(self.name),
+                force_str(self.name),
                 self.quota,
                 self.default_mailbox_quota,
                 self.enabled
diff --git a/modoboa/admin/models/domain_alias.py b/modoboa/admin/models/domain_alias.py
index 2bdd95c51..c312f34ec 100644
--- a/modoboa/admin/models/domain_alias.py
+++ b/modoboa/admin/models/domain_alias.py
@@ -4,8 +4,8 @@ from reversion import revisions as reversion
 
 from django.contrib.contenttypes.fields import GenericRelation
 from django.db import models
-from django.utils.encoding import smart_text
-from django.utils.translation import ugettext as _, ugettext_lazy
+from django.utils.encoding import smart_str
+from django.utils.translation import gettext as _, gettext_lazy
 
 from modoboa.core import models as core_models, signals as core_signals
 from modoboa.lib.exceptions import BadRequest, Conflict
@@ -30,16 +30,16 @@ class DomainAlias(AdminObject):
 
     """Domain aliases."""
 
-    name = models.CharField(ugettext_lazy("name"), max_length=100, unique=True,
-                            help_text=ugettext_lazy("The alias name"))
+    name = models.CharField(gettext_lazy("name"), max_length=100, unique=True,
+                            help_text=gettext_lazy("The alias name"))
     target = models.ForeignKey(
-        Domain, verbose_name=ugettext_lazy("target"),
-        help_text=ugettext_lazy("The domain this alias points to"),
+        Domain, verbose_name=gettext_lazy("target"),
+        help_text=gettext_lazy("The domain this alias points to"),
         on_delete=models.CASCADE
     )
     enabled = models.BooleanField(
-        ugettext_lazy("enabled"),
-        help_text=ugettext_lazy("Check to activate this alias"),
+        gettext_lazy("enabled"),
+        help_text=gettext_lazy("Check to activate this alias"),
         default=True
     )
 
@@ -51,7 +51,7 @@ class DomainAlias(AdminObject):
         app_label = "admin"
 
     def __str__(self):
-        return smart_text(self.name)
+        return smart_str(self.name)
 
     def from_csv(self, user, row):
         """Create a domain alias from a CSV row
diff --git a/modoboa/admin/models/mailbox.py b/modoboa/admin/models/mailbox.py
index 4f0021429..fd2612ab1 100644
--- a/modoboa/admin/models/mailbox.py
+++ b/modoboa/admin/models/mailbox.py
@@ -6,8 +6,8 @@ from django.contrib.contenttypes.models import ContentType
 from django.db import models
 from django.db.models import Q
 from django.db.models.manager import Manager
-from django.utils.encoding import smart_text, force_text
-from django.utils.translation import ugettext as _, ugettext_lazy
+from django.utils.encoding import smart_str, force_str
+from django.utils.translation import gettext as _, gettext_lazy
 
 from modoboa.core.models import User
 from modoboa.lib import exceptions as lib_exceptions
@@ -89,15 +89,15 @@ class Mailbox(mixins.MessageLimitMixin, AdminObject):
     """User mailbox."""
 
     address = models.CharField(
-        ugettext_lazy("address"), max_length=252,
-        help_text=ugettext_lazy(
+        gettext_lazy("address"), max_length=252,
+        help_text=gettext_lazy(
             "Mailbox address (without the @domain.tld part)")
     )
     quota = models.PositiveIntegerField(default=0)
     use_domain_quota = models.BooleanField(default=False)
     message_limit = models.PositiveIntegerField(
-        ugettext_lazy("Message sending limit"), null=True, blank=True,
-        help_text=ugettext_lazy(
+        gettext_lazy("Message sending limit"), null=True, blank=True,
+        help_text=gettext_lazy(
             "Number of messages this mailbox can send per day")
     )
     domain = models.ForeignKey(Domain, on_delete=models.CASCADE)
@@ -115,7 +115,7 @@ class Mailbox(mixins.MessageLimitMixin, AdminObject):
         self.old_message_limit = self.message_limit
 
     def __str__(self):
-        return smart_text(self.full_address)
+        return smart_str(self.full_address)
 
     def __full_address(self, localpart):
         return "%s@%s" % (localpart, self.domain.name)
@@ -154,7 +154,7 @@ class Mailbox(mixins.MessageLimitMixin, AdminObject):
             if code:
                 raise lib_exceptions.InternalError(
                     _("Failed to retrieve mailbox location (%s)") % output)
-            self.__mail_home = force_text(output.strip())
+            self.__mail_home = force_str(output.strip())
         return self.__mail_home
 
     @property
@@ -363,7 +363,7 @@ class SenderAddress(models.Model):
 
     def __str__(self):
         """Return address."""
-        return smart_text(self.address)
+        return smart_str(self.address)
 
 
 reversion.register(SenderAddress)
diff --git a/modoboa/admin/signals.py b/modoboa/admin/signals.py
index 9610ec7bd..756ddb9c8 100644
--- a/modoboa/admin/signals.py
+++ b/modoboa/admin/signals.py
@@ -2,31 +2,22 @@
 
 import django.dispatch
 
-check_extra_account_form = django.dispatch.Signal(
-    providing_args=["account", "form"])
-extra_account_dashboard_widgets = django.dispatch.Signal(
-    providing_args=["user", "account"])
-extra_account_forms = django.dispatch.Signal(
-    providing_args=["user", "account"])
-extra_admin_content = django.dispatch.Signal(
-    providing_args=["user", "location", "currentpage"])
-extra_domain_actions = django.dispatch.Signal(
-    providing_args=["user", "domain"])
-extra_domain_dashboard_widgets = django.dispatch.Signal(
-    providing_args=["user", "domain"])
+check_extra_account_form = django.dispatch.Signal() # Provides account, form
+extra_account_dashboard_widgets = django.dispatch.Signal() # Provides user, account
+extra_account_forms = django.dispatch.Signal() # Provides user, account
+extra_admin_content = django.dispatch.Signal() # Provides user, location, currentpage
+extra_domain_actions = django.dispatch.Signal() # Provides user, domain
+extra_domain_dashboard_widgets = django.dispatch.Signal() # Provides user, domain
 extra_domain_filters = django.dispatch.Signal()
-extra_domain_forms = django.dispatch.Signal(providing_args=["user", "domain"])
-extra_domain_menu_entries = django.dispatch.Signal(providing_args=["user"])
-extra_domain_qset_filters = django.dispatch.Signal(
-    providing_args=["domfilter", "extrafilters"])
+extra_domain_forms = django.dispatch.Signal() # Provides user, domain
+extra_domain_menu_entries = django.dispatch.Signal() # Provides user
+extra_domain_qset_filters = django.dispatch.Signal() # Provides domfilter, extrafilters
 # extra_domain_types = django.dispatch.Signal()
 extra_domain_wizard_steps = django.dispatch.Signal()
-get_account_form_instances = django.dispatch.Signal(
-    providing_args=["user", "account"])
-get_domain_form_instances = django.dispatch.Signal(
-    providing_args=["user", "domain"])
+get_account_form_instances = django.dispatch.Signal() # Provides user, account
+get_domain_form_instances = django.dispatch.Signal() # Provides user, domain
 # get_domain_tags = django.dispatch.Signal(providing_args=["domain"])
-import_object = django.dispatch.Signal(providing_args=["objtype"])
-use_external_recipients = django.dispatch.Signal(providing_args=["recipients"])
-new_dkim_keys = django.dispatch.Signal(providing_args=["domains"])
-extra_account_identities_actions = django.dispatch.Signal(providing_args=["account"])
\ No newline at end of file
+import_object = django.dispatch.Signal() # Provides objtype
+use_external_recipients = django.dispatch.Signal() # Provides recipients
+new_dkim_keys = django.dispatch.Signal() # Provides domain
+extra_account_identities_actions = django.dispatch.Signal() # Provides account
diff --git a/modoboa/admin/templatetags/admin_tags.py b/modoboa/admin/templatetags/admin_tags.py
index c6e93bf44..1e7e74bb8 100644
--- a/modoboa/admin/templatetags/admin_tags.py
+++ b/modoboa/admin/templatetags/admin_tags.py
@@ -6,7 +6,7 @@ from django import template
 from django.template.loader import render_to_string
 from django.urls import reverse
 from django.utils.safestring import mark_safe
-from django.utils.translation import ugettext as _, ugettext_lazy
+from django.utils.translation import gettext as _, gettext_lazy
 
 from modoboa.core import signals as core_signals
 from modoboa.lib.templatetags.lib_tags import render_link
@@ -16,7 +16,7 @@ from .. import signals
 register = template.Library()
 
 genders = {
-    "Enabled": (ugettext_lazy("enabled_m"), ugettext_lazy("enabled_f"))
+    "Enabled": (gettext_lazy("enabled_m"), gettext_lazy("enabled_f"))
 }
 
 
diff --git a/modoboa/admin/tests/test_export.py b/modoboa/admin/tests/test_export.py
index 2ff43176b..9317dd7ad 100644
--- a/modoboa/admin/tests/test_export.py
+++ b/modoboa/admin/tests/test_export.py
@@ -5,7 +5,7 @@ from io import StringIO
 
 from django.core.management import call_command
 from django.urls import reverse
-from django.utils.encoding import force_text
+from django.utils.encoding import force_str
 
 from modoboa.lib.tests import ModoTestCase
 from .. import factories, models
@@ -50,7 +50,7 @@ class ExportTestCase(ModoTestCase):
         ]
         self.assertCountEqual(
             expected_response,
-            force_text(response.content.strip()).split("\r\n")
+            force_str(response.content.strip()).split("\r\n")
         )
 
         # Test management command too.
@@ -59,12 +59,12 @@ class ExportTestCase(ModoTestCase):
         response = sys.stdout.getvalue()
         sys.stdout = stdout_backup
         self.assertCountEqual(
-            expected_response, force_text(response.strip()).split("\r\n"))
+            expected_response, force_str(response.strip()).split("\r\n"))
 
     def test_export_identities(self):
         response = self.__export_identities()
         expected_response = "account;admin;;;;True;SuperAdmins;;\r\naccount;admin@test.com;{PLAIN}toto;;;True;DomainAdmins;admin@test.com;10;test.com\r\naccount;admin@test2.com;{PLAIN}toto;;;True;DomainAdmins;admin@test2.com;10;test2.com\r\naccount;user@test.com;{PLAIN}toto;;;True;SimpleUsers;user@test.com;10\r\naccount;user@test2.com;{PLAIN}toto;;;True;SimpleUsers;user@test2.com;10\r\nalias;alias@test.com;True;user@test.com\r\nalias;forward@test.com;True;user@external.com\r\nalias;postmaster@test.com;True;test@truc.fr;toto@titi.com\r\n"  # NOQA:E501
-        received_content = force_text(response.content.strip()).split("\r\n")
+        received_content = force_str(response.content.strip()).split("\r\n")
         # Empty admin password because it is hashed using SHA512-CRYPT
         admin_row = received_content[0].split(";")
         admin_row[2] = ""
@@ -86,7 +86,7 @@ class ExportTestCase(ModoTestCase):
         expected_response = "account;user@test.com;{PLAIN}toto;;;True;SimpleUsers;user@test.com;10\r\naccount;user@test2.com;{PLAIN}toto;;;True;SimpleUsers;user@test2.com;10\r\naccount;toto@test.com;{PLAIN}toto;Léon;;True;SimpleUsers;toto@test.com;10"  # NOQA:E501
         self.assertCountEqual(
             expected_response.split("\r\n"),
-            force_text(response.content.strip()).split("\r\n")
+            force_str(response.content.strip()).split("\r\n")
         )
 
     def test_export_superadmins(self):
@@ -111,7 +111,7 @@ class ExportTestCase(ModoTestCase):
         expected_response = "account;admin@test.com;{PLAIN}toto;;;True;DomainAdmins;admin@test.com;10;test.com\r\naccount;admin@test2.com;{PLAIN}toto;;;True;DomainAdmins;admin@test2.com;10;test2.com"  # NOQA:E501
         self.assertCountEqual(
             expected_response.split("\r\n"),
-            force_text(response.content.strip()).split("\r\n")
+            force_str(response.content.strip()).split("\r\n")
         )
 
     def test_export_aliases(self):
diff --git a/modoboa/admin/tests/test_mx.py b/modoboa/admin/tests/test_mx.py
index 8505d3666..c15f5ef95 100644
--- a/modoboa/admin/tests/test_mx.py
+++ b/modoboa/admin/tests/test_mx.py
@@ -8,7 +8,7 @@ from testfixtures import LogCapture
 from django.core import mail, management
 from django.test import override_settings
 from django.urls import reverse
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from modoboa.core import factories as core_factories
 from modoboa.lib.tests import ModoTestCase
@@ -221,7 +221,7 @@ class DNSBLTestCase(ModoTestCase):
         management.call_command(
             "modo", "check_mx", "--email", "user@example.test")
         self.assertEqual(len(mail.outbox), 2)
-    
+
     @mock.patch("gevent.socket.gethostbyname")
     @mock.patch("socket.getaddrinfo")
     @mock.patch.object(dns.resolver.Resolver, "resolve")
diff --git a/modoboa/admin/views/alias.py b/modoboa/admin/views/alias.py
index 3271cc48e..b22132dca 100644
--- a/modoboa/admin/views/alias.py
+++ b/modoboa/admin/views/alias.py
@@ -7,7 +7,7 @@ from django.contrib.auth.decorators import login_required, permission_required
 from django.db import IntegrityError
 from django.shortcuts import render
 from django.urls import reverse
-from django.utils.translation import ugettext as _, ungettext
+from django.utils.translation import gettext as _, ngettext
 from django.views import generic
 from django.views.decorators.http import require_http_methods
 
@@ -102,7 +102,7 @@ def delalias(request):
         if not request.user.can_access(alias):
             raise PermDeniedException
         alias.delete()
-    msg = ungettext("Alias deleted", "Aliases deleted", len(selection))
+    msg = ngettext("Alias deleted", "Aliases deleted", len(selection))
     return render_to_json_response(msg)
 
 
diff --git a/modoboa/admin/views/dns.py b/modoboa/admin/views/dns.py
index 42d1738de..3a46b84c5 100644
--- a/modoboa/admin/views/dns.py
+++ b/modoboa/admin/views/dns.py
@@ -1,7 +1,7 @@
 """DNSBL related views."""
 
 from django.contrib.auth import mixins as auth_mixins
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 from django.views import generic
 
 from .. import models
diff --git a/modoboa/admin/views/domain.py b/modoboa/admin/views/domain.py
index 6797f04e3..83c1218e9 100644
--- a/modoboa/admin/views/domain.py
+++ b/modoboa/admin/views/domain.py
@@ -13,7 +13,7 @@ from django.http import HttpResponseRedirect
 from django.shortcuts import render
 from django.template.loader import render_to_string
 from django.urls import reverse
-from django.utils.translation import ugettext as _, ungettext
+from django.utils.translation import gettext as _, ngettext
 from django.views import generic
 from django.views.decorators.csrf import ensure_csrf_cookie
 from django.views.decorators.http import require_http_methods
@@ -247,7 +247,7 @@ def deldomain(request, dom_id):
         raise PermDeniedException(_("You can't delete your own domain"))
     dom.delete(request.user, keepdir)
 
-    msg = ungettext("Domain deleted", "Domains deleted", 1)
+    msg = ngettext("Domain deleted", "Domains deleted", 1)
     return render_to_json_response(msg)
 
 
diff --git a/modoboa/admin/views/export.py b/modoboa/admin/views/export.py
index 183206f2a..b395a1865 100644
--- a/modoboa/admin/views/export.py
+++ b/modoboa/admin/views/export.py
@@ -9,7 +9,7 @@ from django.contrib.auth.decorators import (
 from django.http import HttpResponse
 from django.shortcuts import render
 from django.urls import reverse
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from ..forms import ExportDataForm
 from ..lib import get_domains, get_identities
diff --git a/modoboa/admin/views/identity.py b/modoboa/admin/views/identity.py
index f2b8ab869..2d9ea3786 100644
--- a/modoboa/admin/views/identity.py
+++ b/modoboa/admin/views/identity.py
@@ -8,7 +8,7 @@ from django.contrib.auth.decorators import (
 )
 from django.shortcuts import render
 from django.template.loader import render_to_string
-from django.utils.translation import ugettext as _, ungettext
+from django.utils.translation import gettext as _, ngettext
 from django.views import generic
 from django.views.decorators.csrf import ensure_csrf_cookie
 from django.views.decorators.http import require_http_methods
@@ -191,7 +191,7 @@ def editaccount(request, pk):
 def delaccount(request, pk):
     User.objects.get(pk=pk).delete()
     return render_to_json_response(
-        ungettext("Account deleted", "Accounts deleted", 1)
+        ngettext("Account deleted", "Accounts deleted", 1)
     )
 
 
diff --git a/modoboa/admin/views/import_.py b/modoboa/admin/views/import_.py
index ed5f883a8..575eb3be1 100644
--- a/modoboa/admin/views/import_.py
+++ b/modoboa/admin/views/import_.py
@@ -11,8 +11,8 @@ from django.contrib.auth.decorators import (
 from django.db import transaction
 from django.shortcuts import render
 from django.urls import reverse
-from django.utils.encoding import smart_text
-from django.utils.translation import ugettext as _
+from django.utils.encoding import smart_str
+from django.utils.translation import gettext as _
 
 from modoboa.lib.exceptions import Conflict, ModoboaException
 from .. import lib
diff --git a/modoboa/admin/views/user.py b/modoboa/admin/views/user.py
index 8edc6fa09..f21de52c7 100644
--- a/modoboa/admin/views/user.py
+++ b/modoboa/admin/views/user.py
@@ -4,7 +4,7 @@ from reversion import revisions as reversion
 
 from django.contrib.auth.decorators import login_required
 from django.template.loader import render_to_string
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from modoboa.lib.web_utils import render_to_json_response
 from ..forms import ForwardForm
diff --git a/modoboa/core/api/v1/serializers.py b/modoboa/core/api/v1/serializers.py
index 0e0256857..39e9ff6e1 100644
--- a/modoboa/core/api/v1/serializers.py
+++ b/modoboa/core/api/v1/serializers.py
@@ -1,6 +1,6 @@
 """Core API serializers."""
 
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from rest_framework import serializers
 
diff --git a/modoboa/core/api/v1/viewsets.py b/modoboa/core/api/v1/viewsets.py
index 7c4bf11f1..31a44fa25 100644
--- a/modoboa/core/api/v1/viewsets.py
+++ b/modoboa/core/api/v1/viewsets.py
@@ -1,6 +1,6 @@
 """Core API viewsets."""
 
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 import django_otp
 from django_otp.plugins.otp_static.models import StaticDevice, StaticToken
diff --git a/modoboa/core/api/v2/serializers.py b/modoboa/core/api/v2/serializers.py
index f766fd6ce..56cf3866d 100644
--- a/modoboa/core/api/v2/serializers.py
+++ b/modoboa/core/api/v2/serializers.py
@@ -13,10 +13,10 @@ from django.core.exceptions import ValidationError as djangoValidationError
 from django.template import loader
 
 from django.utils import formats
-from django.utils.encoding import force_text
+from django.utils.encoding import force_str
 from django.utils.http import urlsafe_base64_encode, urlsafe_base64_decode
 from django.utils.encoding import force_bytes
-from django.utils.translation import ugettext_lazy, ugettext as _
+from django.utils.translation import gettext_lazy, gettext as _
 
 from rest_framework import serializers, status
 from rest_framework.exceptions import APIException
@@ -36,7 +36,7 @@ class CustomValidationError(APIException):
         if detail is not None:
             self.detail = detail
         else:
-            self.detail = {'detail': force_text(self.default_detail)}
+            self.detail = {'detail': force_str(self.default_detail)}
 
 
 class NoSMSAvailable(Exception):
@@ -57,7 +57,7 @@ class CoreGlobalParametersSerializer(serializers.Serializer):
 
     # General settings
     authentication_type = serializers.ChoiceField(
-        choices=[("local", ugettext_lazy("Local")),
+        choices=[("local", gettext_lazy("Local")),
                  ("ldap", "LDAP")],
         default="local"
     )
@@ -65,11 +65,11 @@ class CoreGlobalParametersSerializer(serializers.Serializer):
         choices=[("sha512crypt", "sha512crypt"),
                  ("sha256crypt", "sha256crypt"),
                  ("blfcrypt", "bcrypt"),
-                 ("md5crypt", ugettext_lazy("md5crypt (weak)")),
-                 ("sha256", ugettext_lazy("sha256 (weak)")),
-                 ("md5", ugettext_lazy("md5 (weak)")),
-                 ("crypt", ugettext_lazy("crypt (weak)")),
-                 ("plain", ugettext_lazy("plain (weak)"))],
+                 ("md5crypt", gettext_lazy("md5crypt (weak)")),
+                 ("sha256", gettext_lazy("sha256 (weak)")),
+                 ("md5", gettext_lazy("md5 (weak)")),
+                 ("crypt", gettext_lazy("crypt (weak)")),
+                 ("plain", gettext_lazy("plain (weak)"))],
         default="sha512crypt"
     )
     rounds_number = serializers.IntegerField(default=70000)
diff --git a/modoboa/core/api/v2/views.py b/modoboa/core/api/v2/views.py
index 32e07c503..4f69225dc 100644
--- a/modoboa/core/api/v2/views.py
+++ b/modoboa/core/api/v2/views.py
@@ -3,7 +3,7 @@
 import logging
 
 from django.utils.html import escape
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 from django.utils.datastructures import MultiValueDictKeyError
 
 from django.contrib.auth import login
diff --git a/modoboa/core/app_settings.py b/modoboa/core/app_settings.py
index 46e83ee7d..ad817c961 100644
--- a/modoboa/core/app_settings.py
+++ b/modoboa/core/app_settings.py
@@ -5,7 +5,7 @@ import collections
 from django import forms
 from django.conf import settings
 from django.contrib.auth import password_validation
-from django.utils.translation import ugettext as _, ugettext_lazy
+from django.utils.translation import gettext as _, gettext_lazy
 
 from modoboa.core.password_hashers import get_dovecot_schemes
 from modoboa.core.password_hashers.base import PasswordHasher
@@ -36,61 +36,61 @@ class GeneralParametersForm(param_forms.AdminParametersForm):
 
     app = "core"
 
-    sep1 = SeparatorField(label=ugettext_lazy("Authentication"))
+    sep1 = SeparatorField(label=gettext_lazy("Authentication"))
 
     authentication_type = forms.ChoiceField(
-        label=ugettext_lazy("Authentication type"),
-        choices=[("local", ugettext_lazy("Local")),
+        label=gettext_lazy("Authentication type"),
+        choices=[("local", gettext_lazy("Local")),
                  ("ldap", "LDAP")],
         initial="local",
-        help_text=ugettext_lazy("The backend used for authentication"),
+        help_text=gettext_lazy("The backend used for authentication"),
         widget=HorizontalRadioSelect()
     )
 
     password_scheme = forms.ChoiceField(
-        label=ugettext_lazy("Default password scheme"),
+        label=gettext_lazy("Default password scheme"),
         choices=[],
         initial="sha512crypt",
-        help_text=ugettext_lazy("Scheme used to crypt mailbox passwords"),
+        help_text=gettext_lazy("Scheme used to crypt mailbox passwords"),
     )
 
     rounds_number = forms.IntegerField(
-        label=ugettext_lazy("Rounds"),
+        label=gettext_lazy("Rounds"),
         initial=70000,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Number of rounds to use (only used by sha256crypt and "
             "sha512crypt). Must be between 1000 and 999999999, inclusive."
         ),
     )
 
     update_scheme = YesNoField(
-        label=ugettext_lazy("Update password scheme at login"),
+        label=gettext_lazy("Update password scheme at login"),
         initial=True,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Update user password at login to use the default password scheme"
         )
     )
 
     default_password = forms.CharField(
-        label=ugettext_lazy("Default password"),
+        label=gettext_lazy("Default password"),
         initial="password",
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Default password for automatically created accounts.")
     )
 
     random_password_length = forms.IntegerField(
-        label=ugettext_lazy("Random password length"),
+        label=gettext_lazy("Random password length"),
         min_value=8,
         initial=8,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Length of randomly generated passwords.")
     )
 
     update_password_url = forms.URLField(
-        label=ugettext_lazy("Update password service URL"),
+        label=gettext_lazy("Update password service URL"),
         initial="",
         required=False,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "The URL of an external page where users will be able"
             " to update their password. It applies only to non local"
             " users, ie. those automatically created after a successful"
@@ -99,92 +99,92 @@ class GeneralParametersForm(param_forms.AdminParametersForm):
     )
 
     password_recovery_msg = forms.CharField(
-        label=ugettext_lazy("Password recovery announcement"),
+        label=gettext_lazy("Password recovery announcement"),
         initial="",
         required=False,
         widget=forms.widgets.Textarea(),
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "A temporary message that will be displayed on the "
             "reset password page."
         )
     )
 
     sms_password_recovery = YesNoField(
-        label=ugettext_lazy("Enable password recovery by SMS"),
+        label=gettext_lazy("Enable password recovery by SMS"),
         initial=False,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Enable password recovery by SMS for users who filled "
             "a phone number."
         )
     )
 
     sms_provider = forms.ChoiceField(
-        label=ugettext_lazy("SMS provider"),
+        label=gettext_lazy("SMS provider"),
         choices=constants.SMS_BACKENDS,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Choose a provider to send password recovery SMS"
         ),
         required=False
     )
 
     # LDAP specific settings
-    ldap_sep = SeparatorField(label=ugettext_lazy("LDAP settings"))
+    ldap_sep = SeparatorField(label=gettext_lazy("LDAP settings"))
 
     ldap_server_address = forms.CharField(
-        label=ugettext_lazy("Server address"),
+        label=gettext_lazy("Server address"),
         initial="localhost",
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "The IP address or the DNS name of the LDAP server"),
     )
 
     ldap_server_port = forms.IntegerField(
-        label=ugettext_lazy("Server port"),
+        label=gettext_lazy("Server port"),
         initial=389,
-        help_text=ugettext_lazy("The TCP port number used by the LDAP server"),
+        help_text=gettext_lazy("The TCP port number used by the LDAP server"),
     )
 
     ldap_enable_secondary_server = YesNoField(
-        label=ugettext_lazy("Enable secondary server (fallback)"),
+        label=gettext_lazy("Enable secondary server (fallback)"),
         initial=False,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Enable a secondary LDAP server which will be used "
             "if the primary one fails"
         )
     )
 
     ldap_secondary_server_address = forms.CharField(
-        label=ugettext_lazy("Secondary server address"),
+        label=gettext_lazy("Secondary server address"),
         initial="localhost",
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "The IP address or the DNS name of the seondary LDAP server"),
     )
 
     ldap_secondary_server_port = forms.IntegerField(
-        label=ugettext_lazy("Secondary server port"),
+        label=gettext_lazy("Secondary server port"),
         initial=389,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "The TCP port number used by the LDAP secondary server"),
     )
 
     ldap_secured = forms.ChoiceField(
-        label=ugettext_lazy("Use a secured connection"),
+        label=gettext_lazy("Use a secured connection"),
         choices=constants.LDAP_SECURE_MODES,
         initial="none",
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Use an SSL/STARTTLS connection to access the LDAP server")
     )
 
     ldap_is_active_directory = YesNoField(
-        label=ugettext_lazy("Active Directory"),
+        label=gettext_lazy("Active Directory"),
         initial=False,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Tell if the LDAP server is an Active Directory one")
     )
 
     ldap_admin_groups = forms.CharField(
-        label=ugettext_lazy("Administrator groups"),
+        label=gettext_lazy("Administrator groups"),
         initial="",
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Members of those LDAP Posix groups will be created as domain "
             "administrators. Use ';' characters to separate groups."
         ),
@@ -192,45 +192,45 @@ class GeneralParametersForm(param_forms.AdminParametersForm):
     )
 
     ldap_group_type = forms.ChoiceField(
-        label=ugettext_lazy("Group type"),
+        label=gettext_lazy("Group type"),
         initial="posixgroup",
         choices=constants.LDAP_GROUP_TYPES,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "The LDAP group type to use with your directory."
         )
     )
 
     ldap_groups_search_base = forms.CharField(
-        label=ugettext_lazy("Groups search base"),
+        label=gettext_lazy("Groups search base"),
         initial="",
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "The distinguished name of the search base used to find groups"
         ),
         required=False
     )
 
     ldap_password_attribute = forms.CharField(
-        label=ugettext_lazy("Password attribute"),
+        label=gettext_lazy("Password attribute"),
         initial="userPassword",
-        help_text=ugettext_lazy("The attribute used to store user passwords"),
+        help_text=gettext_lazy("The attribute used to store user passwords"),
     )
 
     # LDAP authentication settings
     ldap_auth_sep = SeparatorField(
-        label=ugettext_lazy("LDAP authentication settings"))
+        label=gettext_lazy("LDAP authentication settings"))
 
     ldap_auth_method = forms.ChoiceField(
-        label=ugettext_lazy("Authentication method"),
-        choices=[("searchbind", ugettext_lazy("Search and bind")),
-                 ("directbind", ugettext_lazy("Direct bind"))],
+        label=gettext_lazy("Authentication method"),
+        choices=[("searchbind", gettext_lazy("Search and bind")),
+                 ("directbind", gettext_lazy("Direct bind"))],
         initial="searchbind",
-        help_text=ugettext_lazy("Choose the authentication method to use"),
+        help_text=gettext_lazy("Choose the authentication method to use"),
     )
 
     ldap_bind_dn = forms.CharField(
-        label=ugettext_lazy("Bind DN"),
+        label=gettext_lazy("Bind DN"),
         initial="",
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "The distinguished name to use when binding to the LDAP server. "
             "Leave empty for an anonymous bind"
         ),
@@ -238,9 +238,9 @@ class GeneralParametersForm(param_forms.AdminParametersForm):
     )
 
     ldap_bind_password = forms.CharField(
-        label=ugettext_lazy("Bind password"),
+        label=gettext_lazy("Bind password"),
         initial="",
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "The password to use when binding to the LDAP server "
             "(with 'Bind DN')"
         ),
@@ -249,18 +249,18 @@ class GeneralParametersForm(param_forms.AdminParametersForm):
     )
 
     ldap_search_base = forms.CharField(
-        label=ugettext_lazy("Users search base"),
+        label=gettext_lazy("Users search base"),
         initial="",
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "The distinguished name of the search base used to find users"
         ),
         required=False,
     )
 
     ldap_search_filter = forms.CharField(
-        label=ugettext_lazy("Search filter"),
+        label=gettext_lazy("Search filter"),
         initial="(mail=%(user)s)",
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "An optional filter string (e.g. '(objectClass=person)'). "
             "In order to be valid, it must be enclosed in parentheses."
         ),
@@ -268,9 +268,9 @@ class GeneralParametersForm(param_forms.AdminParametersForm):
     )
 
     ldap_user_dn_template = forms.CharField(
-        label=ugettext_lazy("User DN template"),
+        label=gettext_lazy("User DN template"),
         initial="",
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "The template used to construct a user's DN. It should contain "
             "one placeholder (ie. %(user)s)"
         ),
@@ -279,12 +279,12 @@ class GeneralParametersForm(param_forms.AdminParametersForm):
 
     # LDAP sync. settings
     ldap_sync_sep = SeparatorField(
-        label=ugettext_lazy("LDAP synchronization settings"))
+        label=gettext_lazy("LDAP synchronization settings"))
 
     ldap_sync_bind_dn = forms.CharField(
-        label=ugettext_lazy("Bind DN"),
+        label=gettext_lazy("Bind DN"),
         initial="",
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "The distinguished name to use when binding to the LDAP server. "
             "Leave empty for an anonymous bind"
         ),
@@ -292,9 +292,9 @@ class GeneralParametersForm(param_forms.AdminParametersForm):
     )
 
     ldap_sync_bind_password = forms.CharField(
-        label=ugettext_lazy("Bind password"),
+        label=gettext_lazy("Bind password"),
         initial="",
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "The password to use when binding to the LDAP server "
             "(with 'Bind DN')"
         ),
@@ -303,28 +303,28 @@ class GeneralParametersForm(param_forms.AdminParametersForm):
     )
 
     ldap_enable_sync = YesNoField(
-        label=ugettext_lazy("Enable export to LDAP"),
+        label=gettext_lazy("Enable export to LDAP"),
         initial=False,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Enable automatic synchronization between local database and "
             "LDAP directory")
     )
 
     ldap_sync_delete_remote_account = YesNoField(
-        label=ugettext_lazy(
+        label=gettext_lazy(
             "Delete remote LDAP account when local account is deleted"
         ),
         initial=False,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Delete remote LDAP account when local account is deleted, "
             "otherwise it will be disabled."
         )
     )
 
     ldap_sync_account_dn_template = forms.CharField(
-        label=ugettext_lazy("Account DN template"),
+        label=gettext_lazy("Account DN template"),
         initial="",
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "The template used to construct an account's DN. It should contain "
             "one placeholder (ie. %(user)s)"
         ),
@@ -332,27 +332,27 @@ class GeneralParametersForm(param_forms.AdminParametersForm):
     )
 
     ldap_enable_import = YesNoField(
-        label=ugettext_lazy("Enable import from LDAP"),
+        label=gettext_lazy("Enable import from LDAP"),
         initial=False,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Enable account synchronization from LDAP directory to local "
             "database"
         )
     )
 
     ldap_import_search_base = forms.CharField(
-        label=ugettext_lazy("Users search base"),
+        label=gettext_lazy("Users search base"),
         initial="",
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "The distinguished name of the search base used to find users"
         ),
         required=False,
     )
 
     ldap_import_search_filter = forms.CharField(
-        label=ugettext_lazy("Search filter"),
+        label=gettext_lazy("Search filter"),
         initial="(cn=*)",
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "An optional filter string (e.g. '(objectClass=person)'). "
             "In order to be valid, it must be enclosed in parentheses."
         ),
@@ -360,51 +360,51 @@ class GeneralParametersForm(param_forms.AdminParametersForm):
     )
 
     ldap_import_username_attr = forms.CharField(
-        label=ugettext_lazy("Username attribute"),
+        label=gettext_lazy("Username attribute"),
         initial="cn",
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "The name of the LDAP attribute where the username can be found."
         ),
     )
 
     ldap_dovecot_sync = YesNoField(
-        label=ugettext_lazy("Enable Dovecot LDAP sync"),
+        label=gettext_lazy("Enable Dovecot LDAP sync"),
         initial=False,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "LDAP authentication settings will be applied to Dovecot "
             "configuration."
         )
     )
 
     ldap_dovecot_conf_file = forms.CharField(
-        label=ugettext_lazy("Dovecot LDAP config file"),
+        label=gettext_lazy("Dovecot LDAP config file"),
         initial="/etc/dovecot/dovecot-modoboa.conf",
         required=False,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Location of the configuration file which contains "
             "Dovecot LDAP settings."
         )
     )
 
-    dash_sep = SeparatorField(label=ugettext_lazy("Dashboard"))
+    dash_sep = SeparatorField(label=gettext_lazy("Dashboard"))
 
     rss_feed_url = forms.URLField(
-        label=ugettext_lazy("Custom RSS feed"),
+        label=gettext_lazy("Custom RSS feed"),
         required=False,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Display custom RSS feed to resellers and domain administrators"
         )
     )
 
     hide_features_widget = YesNoField(
-        label=ugettext_lazy("Hide features widget"),
+        label=gettext_lazy("Hide features widget"),
         initial=False,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Hide features widget for resellers and domain administrators"
         )
     )
 
-    notif_sep = SeparatorField(label=ugettext_lazy("Notifications"))
+    notif_sep = SeparatorField(label=gettext_lazy("Notifications"))
 
     sender_address = lib_fields.UTF8EmailField(
         label=_("Sender address"),
@@ -414,26 +414,26 @@ class GeneralParametersForm(param_forms.AdminParametersForm):
         )
     )
 
-    api_sep = SeparatorField(label=ugettext_lazy("Public API"))
+    api_sep = SeparatorField(label=gettext_lazy("Public API"))
 
     enable_api_communication = YesNoField(
-        label=ugettext_lazy("Enable communication"),
+        label=gettext_lazy("Enable communication"),
         initial=True,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Enable communication with Modoboa public API")
     )
 
     check_new_versions = YesNoField(
-        label=ugettext_lazy("Check new versions"),
+        label=gettext_lazy("Check new versions"),
         initial=True,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Automatically checks if a newer version is available")
     )
 
     send_new_versions_email = YesNoField(
-        label=ugettext_lazy("Send an email when new versions are found"),
+        label=gettext_lazy("Send an email when new versions are found"),
         initial=False,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Send an email to notify admins about new versions"
         )
     )
@@ -446,14 +446,14 @@ class GeneralParametersForm(param_forms.AdminParametersForm):
     )
 
     send_statistics = YesNoField(
-        label=ugettext_lazy("Send statistics"),
+        label=gettext_lazy("Send statistics"),
         initial=True,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Send statistics to Modoboa public API "
             "(counters and used extensions)")
     )
 
-    sep3 = SeparatorField(label=ugettext_lazy("Miscellaneous"))
+    sep3 = SeparatorField(label=gettext_lazy("Miscellaneous"))
 
     enable_inactive_accounts = YesNoField(
         label=_("Enable inactive account tracking"),
@@ -481,22 +481,22 @@ class GeneralParametersForm(param_forms.AdminParametersForm):
     )
 
     log_maximum_age = forms.IntegerField(
-        label=ugettext_lazy("Maximum log record age"),
+        label=gettext_lazy("Maximum log record age"),
         initial=365,
-        help_text=ugettext_lazy("The maximum age in days of a log record"),
+        help_text=gettext_lazy("The maximum age in days of a log record"),
     )
 
     items_per_page = forms.IntegerField(
-        label=ugettext_lazy("Items per page"),
+        label=gettext_lazy("Items per page"),
         initial=30,
-        help_text=ugettext_lazy("Number of displayed items per page"),
+        help_text=gettext_lazy("Number of displayed items per page"),
     )
 
     default_top_redirection = forms.ChoiceField(
-        label=ugettext_lazy("Default top redirection"),
+        label=gettext_lazy("Default top redirection"),
         choices=[],
         initial="user",
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "The default redirection used when no application is specified"
         ),
     )
@@ -537,7 +537,7 @@ class GeneralParametersForm(param_forms.AdminParametersForm):
         )
         available_schemes = get_dovecot_schemes()
         self.fields["password_scheme"].choices = [
-            (hasher.name, ugettext_lazy(hasher.label))
+            (hasher.name, gettext_lazy(hasher.label))
             for hasher in PasswordHasher.get_password_hashers()
             if hasher().scheme in available_schemes
         ]
@@ -725,46 +725,46 @@ class GeneralParametersForm(param_forms.AdminParametersForm):
 
 GLOBAL_PARAMETERS_STRUCT = collections.OrderedDict([
     ("authentication", {
-        "label": ugettext_lazy("Authentication"),
+        "label": gettext_lazy("Authentication"),
         "params": collections.OrderedDict([
             ("authentication_type", {
-                "label": ugettext_lazy("Authentication type"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Authentication type"),
+                "help_text": gettext_lazy(
                     "The backend used for authentication"),
             }),
             ("password_scheme", {
-                "label": ugettext_lazy("Default password scheme"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Default password scheme"),
+                "help_text": gettext_lazy(
                     "Scheme used to crypt mailbox passwords"),
             }),
             ("rounds_number", {
-                "label": ugettext_lazy("Rounds"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Rounds"),
+                "help_text": gettext_lazy(
                     "Number of rounds to use (only used by sha256crypt and "
                     "sha512crypt). Must be between 1000 and 999999999, "
                     "inclusive."
                 )
             }),
             ("update_scheme", {
-                "label": ugettext_lazy("Update password scheme at login"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Update password scheme at login"),
+                "help_text": gettext_lazy(
                     "Update user password at login to use the default "
                     "password scheme"
                 )
             }),
             ("default_password", {
-                "label": ugettext_lazy("Default password"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Default password"),
+                "help_text": gettext_lazy(
                     "Default password for automatically created accounts.")
             }),
             ("random_password_length", {
-                "label": ugettext_lazy("Random password length"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Random password length"),
+                "help_text": gettext_lazy(
                     "Length of randomly generated passwords.")
             }),
             ("update_password_url", {
-                "label": ugettext_lazy("Update password service URL"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Update password service URL"),
+                "help_text": gettext_lazy(
                     "The URL of an external page where users will be able"
                     " to update their password. It applies only to non local"
                     " users, ie. those automatically created after a successful"
@@ -772,23 +772,23 @@ GLOBAL_PARAMETERS_STRUCT = collections.OrderedDict([
                 )
             }),
             ("password_recovery_msg", {
-                "label": ugettext_lazy("Password recovery announcement"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Password recovery announcement"),
+                "help_text": gettext_lazy(
                     "A temporary message that will be displayed on the "
                     "reset password page."
                 )
             }),
             ("sms_password_recovery", {
-                "label": ugettext_lazy("Enable password recovery by SMS"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Enable password recovery by SMS"),
+                "help_text": gettext_lazy(
                     "Enable password recovery by SMS for users who filled "
                     "a phone number."
                 )
             }),
             ("sms_provider", {
-                "label": ugettext_lazy("SMS provider"),
+                "label": gettext_lazy("SMS provider"),
                 "display": "sms_password_recovery=true",
-                "help_text": ugettext_lazy(
+                "help_text": gettext_lazy(
                     "Choose a provider to send password recovery SMS"
                 )
             }),
@@ -799,94 +799,94 @@ GLOBAL_PARAMETERS_STRUCT = collections.OrderedDict([
         "label": _("LDAP"),
         "params": collections.OrderedDict([
             ("ldap_server_address", {
-                "label": ugettext_lazy("Server address"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Server address"),
+                "help_text": gettext_lazy(
                     "The IP address or the DNS name of the LDAP server"),
             }),
             ("ldap_server_port", {
-                "label": ugettext_lazy("Server port"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Server port"),
+                "help_text": gettext_lazy(
                     "The TCP port number used by the LDAP server")
             }),
             ("ldap_enable_secondary_server", {
-                "label": ugettext_lazy("Enable secondary server (fallback)"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Enable secondary server (fallback)"),
+                "help_text": gettext_lazy(
                     "Enable a secondary LDAP server which will be used "
                     "if the primary one fails"
                 )
             }),
             ("ldap_secondary_server_address", {
-                "label": ugettext_lazy("Secondary server address"),
+                "label": gettext_lazy("Secondary server address"),
                 "display": "ldap_enable_secondary_server=true",
-                "help_text": ugettext_lazy(
+                "help_text": gettext_lazy(
                     "The IP address or the DNS name of the seondary LDAP server"
                 )
             }),
             ("ldap_secondary_server_port", {
-                "label": ugettext_lazy("Secondary server port"),
+                "label": gettext_lazy("Secondary server port"),
                 "display": "ldap_enable_secondary_server=true",
-                "help_text": ugettext_lazy(
+                "help_text": gettext_lazy(
                     "The TCP port number used by the LDAP secondary server"
                 )
             }),
             ("ldap_secured", {
-                "label": ugettext_lazy("Use a secured connection"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Use a secured connection"),
+                "help_text": gettext_lazy(
                     "Use an SSL/STARTTLS connection to access the LDAP server")
             }),
             ("ldap_is_active_directory", {
-                "label": ugettext_lazy("Active Directory"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Active Directory"),
+                "help_text": gettext_lazy(
                     "Tell if the LDAP server is an Active Directory one")
             }),
             ("ldap_admin_groups", {
-                "label": ugettext_lazy("Administrator groups"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Administrator groups"),
+                "help_text": gettext_lazy(
                     "Members of those LDAP Posix groups will be created as "
                     "domain administrators. Use ';' characters to separate "
                     "groups."
                 )
             }),
             ("ldap_group_type", {
-                "label": ugettext_lazy("Group type"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Group type"),
+                "help_text": gettext_lazy(
                     "The LDAP group type to use with your directory."
                 )
             }),
             ("ldap_groups_search_base", {
-                "label": ugettext_lazy("Groups search base"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Groups search base"),
+                "help_text": gettext_lazy(
                     "The distinguished name of the search base used to find "
                     "groups"
                 )
             }),
             ("ldap_password_attribute", {
-                "label": ugettext_lazy("Password attribute"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Password attribute"),
+                "help_text": gettext_lazy(
                     "The attribute used to store user passwords"),
             }),
             ("ldap_auth_sep", {
-                "label": ugettext_lazy("LDAP authentication settings"),
+                "label": gettext_lazy("LDAP authentication settings"),
                 "display": "authentication_type=ldap",
                 "separator": True
             }),
             ("ldap_auth_method", {
-                "label": ugettext_lazy("Authentication method"),
+                "label": gettext_lazy("Authentication method"),
                 "display": "authentication_type=ldap",
-                "help_text": ugettext_lazy(
+                "help_text": gettext_lazy(
                     "Choose the authentication method to use"),
             }),
             ("ldap_bind_dn", {
-                "label": ugettext_lazy("Bind DN"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Bind DN"),
+                "help_text": gettext_lazy(
                     "The distinguished name to use when binding to the LDAP "
                     "server. Leave empty for an anonymous bind"
                 ),
                 "display": "authentication_type=ldap&ldap_auth_method=searchbind"
             }),
             ("ldap_bind_password", {
-                "label": ugettext_lazy("Bind password"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Bind password"),
+                "help_text": gettext_lazy(
                     "The password to use when binding to the LDAP server "
                     "(with 'Bind DN')"
                 ),
@@ -894,113 +894,113 @@ GLOBAL_PARAMETERS_STRUCT = collections.OrderedDict([
                 "password": True
             }),
             ("ldap_search_base", {
-                "label": ugettext_lazy("Users search base"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Users search base"),
+                "help_text": gettext_lazy(
                     "The distinguished name of the search base used to find "
                     "users"
                 ),
                 "display": "authentication_type=ldap&ldap_auth_method=searchbind"
             }),
             ("ldap_search_filter", {
-                "label": ugettext_lazy("Search filter"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Search filter"),
+                "help_text": gettext_lazy(
                     "An optional filter string (e.g. '(objectClass=person)'). "
                     "In order to be valid, it must be enclosed in parentheses."
                 ),
                 "display": "authentication_type=ldap&ldap_auth_method=searchbind"
             }),
             ("ldap_user_dn_template", {
-                "label": ugettext_lazy("User DN template"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("User DN template"),
+                "help_text": gettext_lazy(
                     "The template used to construct a user's DN. It should "
                     "contain one placeholder (ie. %(user)s)"
                 ),
                 "display": "authentication_type=ldap&ldap_auth_method=directbind"
             }),
             ("ldap_sync_sep", {
-                "label": ugettext_lazy("LDAP synchronization settings"),
+                "label": gettext_lazy("LDAP synchronization settings"),
                 "separator": True
             }),
             ("ldap_sync_bind_dn", {
-                "label": ugettext_lazy("Bind DN"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Bind DN"),
+                "help_text": gettext_lazy(
                     "The distinguished name to use when binding to the LDAP server. "
                     "Leave empty for an anonymous bind"
                 )
             }),
             ("ldap_sync_bind_password", {
-                "label": ugettext_lazy("Bind password"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Bind password"),
+                "help_text": gettext_lazy(
                     "The password to use when binding to the LDAP server "
                     "(with 'Bind DN')"
                 ),
                 "password": True
             }),
             ("ldap_enable_sync", {
-                "label": ugettext_lazy("Enable export to LDAP"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Enable export to LDAP"),
+                "help_text": gettext_lazy(
                     "Enable automatic synchronization between local database "
                     "and LDAP directory"
                 )
             }),
             ("ldap_sync_delete_remote_account", {
-                "label": ugettext_lazy(
+                "label": gettext_lazy(
                     "Delete remote LDAP account when local account is deleted"),
-                "help_text": ugettext_lazy(
+                "help_text": gettext_lazy(
                     "Delete remote LDAP account when local account is deleted, "
                     "otherwise it will be disabled."
                 ),
                 "display": "ldap_enable_sync=true"
             }),
             ("ldap_sync_account_dn_template", {
-                "label": ugettext_lazy("Account DN template"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Account DN template"),
+                "help_text": gettext_lazy(
                     "The template used to construct an account's DN. It should "
                     "contain one placeholder (ie. %(user)s)"
                 ),
                 "display": "ldap_enable_sync=true"
             }),
             ("ldap_enable_import", {
-                "label": ugettext_lazy("Enable import from LDAP"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Enable import from LDAP"),
+                "help_text": gettext_lazy(
                     "Enable account synchronization from LDAP directory to "
                     "local database"
                 )
             }),
             ("ldap_import_search_base", {
-                "label": ugettext_lazy("Users search base"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Users search base"),
+                "help_text": gettext_lazy(
                     "The distinguished name of the search base used to find "
                     "users"
                 ),
                 "display": "ldap_enable_import=true"
             }),
             ("ldap_import_search_filter", {
-                "label": ugettext_lazy("Search filter"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Search filter"),
+                "help_text": gettext_lazy(
                     "An optional filter string (e.g. '(objectClass=person)'). "
                     "In order to be valid, it must be enclosed in parentheses."
                 ),
                 "display": "ldap_enable_import=true"
             }),
             ("ldap_import_username_attr", {
-                "label": ugettext_lazy("Username attribute"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Username attribute"),
+                "help_text": gettext_lazy(
                     "The name of the LDAP attribute where the username can be "
                     "found."
                 ),
                 "display": "ldap_enable_import=true"
             }),
             ("ldap_dovecot_sync", {
-                "label": ugettext_lazy("Enable Dovecot LDAP sync"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Enable Dovecot LDAP sync"),
+                "help_text": gettext_lazy(
                     "LDAP authentication settings will be applied to Dovecot "
                     "configuration."
                 )
             }),
             ("ldap_dovecot_conf_file", {
-                "label": ugettext_lazy("Dovecot LDAP config file"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Dovecot LDAP config file"),
+                "help_text": gettext_lazy(
                     "Location of the configuration file which contains "
                     "Dovecot LDAP settings."
                 ),
@@ -1010,18 +1010,18 @@ GLOBAL_PARAMETERS_STRUCT = collections.OrderedDict([
         ])
     }),
     ("dashboard", {
-        "label": ugettext_lazy("Dashboard"),
+        "label": gettext_lazy("Dashboard"),
         "params": collections.OrderedDict([
             ("rss_feed_url", {
-                "label": ugettext_lazy("Custom RSS feed"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Custom RSS feed"),
+                "help_text": gettext_lazy(
                     "Display custom RSS feed to resellers and domain "
                     "administrators"
                 )
             }),
             ("hide_features_widget", {
-                "label": ugettext_lazy("Hide features widget"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Hide features widget"),
+                "help_text": gettext_lazy(
                     "Hide features widget for resellers and domain "
                     "administrators"
                 )
@@ -1029,90 +1029,90 @@ GLOBAL_PARAMETERS_STRUCT = collections.OrderedDict([
         ])
     }),
     ("notifications", {
-        "label": ugettext_lazy("Notifications"),
+        "label": gettext_lazy("Notifications"),
         "params": collections.OrderedDict([
             ("sender_address", {
-                "label": ugettext_lazy("Sender address"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Sender address"),
+                "help_text": gettext_lazy(
                     "Email address used to send notifications.")
             })
         ])
     }),
     ("api", {
-        "label": ugettext_lazy("Public API"),
+        "label": gettext_lazy("Public API"),
         "params": collections.OrderedDict([
             ("enable_api_communication", {
-                "label": ugettext_lazy("Enable communication"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Enable communication"),
+                "help_text": gettext_lazy(
                     "Automatically checks if a newer version is available")
             }),
             ("check_new_versions", {
-                "label": ugettext_lazy("Check new versions"),
+                "label": gettext_lazy("Check new versions"),
                 "display": "enable_api_communication=true",
-                "help_text": ugettext_lazy(
+                "help_text": gettext_lazy(
                     "Automatically checks if a newer version is available")
             }),
             ("send_new_versions_email", {
-                "label": ugettext_lazy(
+                "label": gettext_lazy(
                     "Send an email when new versions are found"),
                 "display": "check_new_versions=true",
-                "help_text": ugettext_lazy(
+                "help_text": gettext_lazy(
                     "Send an email to notify admins about new versions"
                 )
             }),
             ("new_versions_email_rcpt", {
-                "label": ugettext_lazy("Recipient"),
+                "label": gettext_lazy("Recipient"),
                 "display": "check_new_versions=true",
-                "help_text": ugettext_lazy(
+                "help_text": gettext_lazy(
                     "Recipient of new versions notification emails."
                 )
             }),
             ("send_statistics", {
-                "label": ugettext_lazy("Send statistics"),
+                "label": gettext_lazy("Send statistics"),
                 "display": "enable_api_communication=true",
-                "help_text": ugettext_lazy(
+                "help_text": gettext_lazy(
                     "Send statistics to Modoboa public API "
                     "(counters and used extensions)")
             })
         ])
     }),
     ("misc", {
-        "label": ugettext_lazy("Miscellaneous"),
+        "label": gettext_lazy("Miscellaneous"),
         "params": collections.OrderedDict([
              ("enable_inactive_accounts", {
-                "label": ugettext_lazy("Enable inactive account tracking"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Enable inactive account tracking"),
+                "help_text": gettext_lazy(
                     "Allow the administrator to set a threshold (in days) "
                     "beyond which an account is considered inactive "
                     "if the user hasn't logged in"
                     ),
             }),
             ("inactive_account_threshold", {
-                "label": ugettext_lazy("Inactive account threshold"),
+                "label": gettext_lazy("Inactive account threshold"),
                 "display": "enable_inactive_accounts=true",
-                "help_text": ugettext_lazy(
+                "help_text": gettext_lazy(
                     "An account with a last login date greater than this "
                     "threshold (in days) will be considered as inactive"
                 )
             }),
             ("top_notifications_check_interval", {
-                "label": ugettext_lazy("Top notifications check interval"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Top notifications check interval"),
+                "help_text": gettext_lazy(
                     "Interval between two top notification checks (in seconds)"
                 ),
             }),
             ("log_maximum_age", {
-                "label": ugettext_lazy("Maximum log record age"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Maximum log record age"),
+                "help_text": gettext_lazy(
                     "The maximum age in days of a log record"),
             }),
             ("items_per_page", {
-                "label": ugettext_lazy("Items per page"),
-                "help_text": ugettext_lazy("Number of displayed items per page")
+                "label": gettext_lazy("Items per page"),
+                "help_text": gettext_lazy("Number of displayed items per page")
             }),
             ("default_top_redirection", {
-                "label": ugettext_lazy("Default top redirection"),
-                "help_text": ugettext_lazy(
+                "label": gettext_lazy("Default top redirection"),
+                "help_text": gettext_lazy(
                     "The default redirection used when no application is "
                     "specified"
                 ),
diff --git a/modoboa/core/apps.py b/modoboa/core/apps.py
index 515174dce..311f497de 100644
--- a/modoboa/core/apps.py
+++ b/modoboa/core/apps.py
@@ -2,7 +2,7 @@
 
 from django.apps import AppConfig
 from django.db.models import signals
-from django.utils.translation import ugettext_lazy
+from django.utils.translation import gettext_lazy
 
 
 def load_core_settings():
@@ -16,9 +16,9 @@ def load_core_settings():
     from .api.v2 import serializers
 
     param_tools.registry.add(
-        "global", app_settings.GeneralParametersForm, ugettext_lazy("General"))
+        "global", app_settings.GeneralParametersForm, gettext_lazy("General"))
     param_tools.registry.add2(
-        "global", "core", ugettext_lazy("General"),
+        "global", "core", gettext_lazy("General"),
         app_settings.GLOBAL_PARAMETERS_STRUCT,
         serializers.CoreGlobalParametersSerializer)
 
diff --git a/modoboa/core/checks/settings_checks.py b/modoboa/core/checks/settings_checks.py
index a1efe49d7..d5858e2e1 100644
--- a/modoboa/core/checks/settings_checks.py
+++ b/modoboa/core/checks/settings_checks.py
@@ -1,6 +1,6 @@
 from django.conf import settings
 from django.core.checks import Warning, register
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 W001 = Warning(
     _("You have USE_TZ set to False, this may result in issues during "
diff --git a/modoboa/core/constants.py b/modoboa/core/constants.py
index a44529c6f..cc9a8b11b 100644
--- a/modoboa/core/constants.py
+++ b/modoboa/core/constants.py
@@ -1,12 +1,12 @@
 """Core application constants."""
 
 from django.conf import settings
-from django.utils.translation import ugettext_lazy
+from django.utils.translation import gettext_lazy
 
-SIMPLEUSERS_ROLE = ("SimpleUsers", ugettext_lazy("Simple user"))
-DOMAINADMINS_ROLE = ("DomainAdmins", ugettext_lazy("Domain administrator"))
-RESELLERS_ROLE = ("Resellers", ugettext_lazy("Reseller"))
-SUPERADMINS_ROLE = ("SuperAdmins", ugettext_lazy("Super administrator"))
+SIMPLEUSERS_ROLE = ("SimpleUsers", gettext_lazy("Simple user"))
+DOMAINADMINS_ROLE = ("DomainAdmins", gettext_lazy("Domain administrator"))
+RESELLERS_ROLE = ("Resellers", gettext_lazy("Reseller"))
+SUPERADMINS_ROLE = ("SuperAdmins", gettext_lazy("Super administrator"))
 
 ROLES = (
     SIMPLEUSERS_ROLE,
@@ -50,14 +50,14 @@ LDAP_GROUP_TYPES = (
 )
 
 LDAP_SECURE_MODES = [
-    ("none", ugettext_lazy("No")),
+    ("none", gettext_lazy("No")),
     ("starttls", "STARTTLS"),
     ("ssl", "SSL/TLS")
 ]
 
 LDAP_AUTH_METHODS = [
-    ("searchbind", ugettext_lazy("Search and bind")),
-    ("directbind", ugettext_lazy("Direct bind"))
+    ("searchbind", gettext_lazy("Search and bind")),
+    ("directbind", gettext_lazy("Direct bind"))
 ]
 
 PERMISSIONS = {
@@ -105,11 +105,11 @@ PERMISSIONS = {
 }
 
 SMS_BACKENDS = [
-    ("", ugettext_lazy("Choose a provider")),
+    ("", gettext_lazy("Choose a provider")),
     ("ovh", "OVH"),
 ]
 
 if settings.DEBUG:
-    SMS_BACKENDS.insert(1, ("dummy", ugettext_lazy("Dummy")))
+    SMS_BACKENDS.insert(1, ("dummy", gettext_lazy("Dummy")))
 
 TFA_DEVICE_TOKEN_KEY = "otp_device_id"
diff --git a/modoboa/core/drf_authentication.py b/modoboa/core/drf_authentication.py
index 1bb9f5c52..9427fca5a 100644
--- a/modoboa/core/drf_authentication.py
+++ b/modoboa/core/drf_authentication.py
@@ -1,7 +1,7 @@
 """Custom authentication for DRF."""
 
 from django.urls import reverse
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import gettext_lazy as _
 
 from django_otp.models import Device
 from drf_spectacular.contrib.rest_framework_simplejwt import SimpleJWTScheme
diff --git a/modoboa/core/extensions.py b/modoboa/core/extensions.py
index 3ea192dee..7d1103eac 100644
--- a/modoboa/core/extensions.py
+++ b/modoboa/core/extensions.py
@@ -1,7 +1,8 @@
 """Extension management."""
 
 from django.conf import settings
-from django.conf.urls import include, url
+from django.conf.urls import include
+from django.urls import re_path
 from django.utils.encoding import smart_str
 
 
@@ -111,7 +112,7 @@ class ExtensionsPool(object):
                 pattern = "{}.urls"
             try:
                 result.append(
-                    url(root, include(pattern.format(ext_name)))
+                    re_path(root, include(pattern.format(ext_name)))
                 )
             except ImportError:
                 # No urls for this extension
diff --git a/modoboa/core/forms.py b/modoboa/core/forms.py
index 3c1d8e0de..61fa248d5 100644
--- a/modoboa/core/forms.py
+++ b/modoboa/core/forms.py
@@ -7,7 +7,7 @@ from django.contrib.auth import (
     forms as auth_forms, get_user_model, password_validation
 )
 from django.db.models import Q
-from django.utils.translation import ugettext as _, ugettext_lazy
+from django.utils.translation import gettext as _, gettext_lazy
 
 import django_otp
 
@@ -20,11 +20,11 @@ class LoginForm(forms.Form):
     """User login form."""
 
     username = forms.CharField(
-        label=ugettext_lazy("Username"),
+        label=gettext_lazy("Username"),
         widget=forms.TextInput(attrs={"class": "form-control"})
     )
     password = forms.CharField(
-        label=ugettext_lazy("Password"),
+        label=gettext_lazy("Password"),
         widget=forms.PasswordInput(attrs={"class": "form-control"})
     )
     rememberme = forms.BooleanField(
@@ -37,15 +37,15 @@ class ProfileForm(forms.ModelForm):
     """Form to update User profile."""
 
     oldpassword = forms.CharField(
-        label=ugettext_lazy("Old password"), required=False,
+        label=gettext_lazy("Old password"), required=False,
         widget=forms.PasswordInput(attrs={"class": "form-control"})
     )
     newpassword = forms.CharField(
-        label=ugettext_lazy("New password"), required=False,
+        label=gettext_lazy("New password"), required=False,
         widget=forms.PasswordInput(attrs={"class": "form-control"})
     )
     confirmation = forms.CharField(
-        label=ugettext_lazy("Confirmation"), required=False,
+        label=gettext_lazy("Confirmation"), required=False,
         widget=forms.PasswordInput(attrs={"class": "form-control"})
     )
 
@@ -115,7 +115,7 @@ class APIAccessForm(forms.Form):
     """Form to control API access."""
 
     enable_api_access = forms.BooleanField(
-        label=ugettext_lazy("Enable API access"), required=False)
+        label=gettext_lazy("Enable API access"), required=False)
 
     def __init__(self, *args, **kwargs):
         """Initialize form."""
@@ -149,7 +149,7 @@ class VerifySMSCodeForm(forms.Form):
     """A form to verify a code received by SMS."""
 
     code = forms.CharField(
-        label=ugettext_lazy("Verification code"),
+        label=gettext_lazy("Verification code"),
         widget=forms.widgets.TextInput(attrs={"class": "form-control"})
     )
 
diff --git a/modoboa/core/handlers.py b/modoboa/core/handlers.py
index a0833c22b..0934cb3d0 100644
--- a/modoboa/core/handlers.py
+++ b/modoboa/core/handlers.py
@@ -9,8 +9,8 @@ from django.contrib.sites import models as sites_models
 from django.db.models import signals
 from django.dispatch import receiver
 from django.urls import reverse
-from django.utils.encoding import smart_text
-from django.utils.translation import ugettext as _
+from django.utils.encoding import smart_str
+from django.utils.translation import gettext as _
 
 from modoboa.lib import exceptions, permissions
 from modoboa.lib.signals import get_request
@@ -39,7 +39,7 @@ def post_revision_commit(sender, **kwargs):
             action = _("modified")
             level = "warning"
         message = _("%(object)s '%(name)s' %(action)s by user %(user)s") % {
-            "object": smart_text(version.content_type).capitalize(),
+            "object": smart_str(version.content_type).capitalize(),
             "name": version.object_repr, "action": action,
             "user": current_user
         }
@@ -61,7 +61,7 @@ def log_object_removal(sender, instance, **kwargs):
         return
     logger = logging.getLogger("modoboa.admin")
     msg = _("%(object)s '%(name)s' %(action)s by ") % {
-        "object": smart_text(version.content_type).capitalize(),
+        "object": smart_str(version.content_type).capitalize(),
         "name": version.object_repr, "action": _("deleted")
     }
     request = get_request()
diff --git a/modoboa/core/management/commands/communicate_with_public_api.py b/modoboa/core/management/commands/communicate_with_public_api.py
index eac121bf3..d5d850621 100644
--- a/modoboa/core/management/commands/communicate_with_public_api.py
+++ b/modoboa/core/management/commands/communicate_with_public_api.py
@@ -3,7 +3,7 @@
 from django.core.mail import EmailMessage
 from django.core.management.base import BaseCommand, CommandError
 from django.template.loader import render_to_string
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from modoboa.admin import models as admin_models
 from modoboa.core.extensions import exts_pool
diff --git a/modoboa/core/migrations/0025_rename_user_email_is_active_core_user_email_c0c03f_idx.py b/modoboa/core/migrations/0025_rename_user_email_is_active_core_user_email_c0c03f_idx.py
new file mode 100644
index 000000000..a001c7257
--- /dev/null
+++ b/modoboa/core/migrations/0025_rename_user_email_is_active_core_user_email_c0c03f_idx.py
@@ -0,0 +1,17 @@
+# Generated by Django 4.2 on 2023-04-25 12:00
+
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ("core", "0024_alter_user_language"),
+    ]
+
+    operations = [
+        migrations.RenameIndex(
+            model_name="user",
+            new_name="core_user_email_c0c03f_idx",
+            old_fields=("email", "is_active"),
+        ),
+    ]
diff --git a/modoboa/core/models.py b/modoboa/core/models.py
index 3cb2ddbf4..efff9e820 100644
--- a/modoboa/core/models.py
+++ b/modoboa/core/models.py
@@ -6,9 +6,9 @@ from email.header import Header
 from django.conf import settings
 from django.db import models
 from django.urls import reverse
-from django.utils.encoding import force_str, smart_bytes, smart_text
+from django.utils.encoding import force_str, smart_bytes, smart_str
 from django.utils.functional import cached_property
-from django.utils.translation import ugettext as _, ugettext_lazy
+from django.utils.translation import gettext as _, gettext_lazy
 
 from django.contrib.auth.models import AbstractUser, Group
 from django.contrib.contenttypes.fields import GenericForeignKey
@@ -49,26 +49,26 @@ class User(AbstractUser):
     is_active = models.BooleanField(default=True, db_index=True)
     is_local = models.BooleanField(default=True, db_index=True)
     master_user = models.BooleanField(
-        ugettext_lazy("Allow mailboxes access"), default=False,
-        help_text=ugettext_lazy(
+        gettext_lazy("Allow mailboxes access"), default=False,
+        help_text=gettext_lazy(
             "Allow this administrator to access user mailboxes"
         )
     )
-    password = models.CharField(ugettext_lazy("password"), max_length=256)
+    password = models.CharField(gettext_lazy("password"), max_length=256)
 
     language = models.CharField(
-        ugettext_lazy("language"),
+        gettext_lazy("language"),
         max_length=10, default="en", choices=constants.LANGUAGES,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Prefered language to display pages."
         )
     )
     phone_number = PhoneNumberField(
-        ugettext_lazy("Phone number"), blank=True, null=True)
+        gettext_lazy("Phone number"), blank=True, null=True)
     secondary_email = models.EmailField(
-        ugettext_lazy("Secondary email"), max_length=254,
+        gettext_lazy("Secondary email"), max_length=254,
         blank=True, null=True,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "An alternative e-mail address, can be used for recovery needs.")
     )
 
@@ -78,9 +78,7 @@ class User(AbstractUser):
 
     class Meta(object):
         ordering = ["username"]
-        index_together = [
-            ["email", "is_active"]
-        ]
+        indexes = [models.Index(fields=["email", "is_active"])]
 
     password_expr = re.compile(r'\{([\w\-]+)\}(.+)')
 
@@ -144,7 +142,7 @@ class User(AbstractUser):
         return hasher().verify(raw_value, val2)
 
     def __str__(self):
-        return smart_text(self.get_username())
+        return smart_str(self.get_username())
 
     def get_absolute_url(self):
         """Return detail url for this user."""
@@ -369,13 +367,13 @@ class User(AbstractUser):
         """Return row that can be included in a CSV file."""
         row = [
             "account",
-            smart_text(self.username),
-            smart_text(self.password),
-            smart_text(self.first_name),
-            smart_text(self.last_name),
-            smart_text(self.is_active),
-            smart_text(self.role),
-            smart_text(self.email)
+            smart_str(self.username),
+            smart_str(self.password),
+            smart_str(self.first_name),
+            smart_str(self.last_name),
+            smart_str(self.is_active),
+            smart_str(self.role),
+            smart_str(self.email)
         ]
         results = signals.account_exported.send(
             sender=self.__class__, user=self)
diff --git a/modoboa/core/password_hashers/__init__.py b/modoboa/core/password_hashers/__init__.py
index bcbf86b3f..aadf96bca 100644
--- a/modoboa/core/password_hashers/__init__.py
+++ b/modoboa/core/password_hashers/__init__.py
@@ -3,7 +3,7 @@ Password hashers for Modoboa.
 """
 
 from django.conf import settings
-from django.utils.encoding import smart_text
+from django.utils.encoding import smart_str
 
 from modoboa.core.password_hashers.advanced import (  # NOQA:F401
     BLFCRYPTHasher, MD5CRYPTHasher, SHA256CRYPTHasher, SHA512CRYPTHasher,
@@ -53,5 +53,5 @@ def get_dovecot_schemes():
             if retcode:
                 schemes = default_schemes
 
-    return ["{{{}}}".format(smart_text(scheme))
+    return ["{{{}}}".format(smart_str(scheme))
             for scheme in schemes.split()]
diff --git a/modoboa/core/password_hashers/advanced.py b/modoboa/core/password_hashers/advanced.py
index dfac9cc99..899b860d6 100644
--- a/modoboa/core/password_hashers/advanced.py
+++ b/modoboa/core/password_hashers/advanced.py
@@ -40,7 +40,7 @@ class BLFCRYPTHasher(PasswordHasher):
         # rounds = parameters.get_global_parameter("rounds_number")
         # To get around this, I use the default of 12.
         rounds = 12
-        return bcrypt.hash(clearvalue, rounds=rounds)
+        return bcrypt.hash.using(rounds=rounds).hash(clearvalue)
 
     def verify(self, clearvalue, hashed_value):
         return bcrypt.verify(clearvalue, hashed_value)
@@ -85,7 +85,7 @@ class SHA256CRYPTHasher(PasswordHasher):
 
     def _encrypt(self, clearvalue, salt=None):
         rounds = param_tools.get_global_parameter("rounds_number")
-        return sha256_crypt.hash(clearvalue, rounds=rounds)
+        return sha256_crypt.using(rounds=rounds).hash(clearvalue)
 
     def verify(self, clearvalue, hashed_value):
         return sha256_crypt.verify(clearvalue, hashed_value)
@@ -107,7 +107,7 @@ class SHA512CRYPTHasher(PasswordHasher):
 
     def _encrypt(self, clearvalue, salt=None):
         rounds = param_tools.get_global_parameter("rounds_number")
-        return sha512_crypt.hash(clearvalue, rounds=rounds)
+        return sha512_crypt.using(rounds=rounds).hash(clearvalue)
 
     def verify(self, clearvalue, hashed_value):
         return sha512_crypt.verify(clearvalue, hashed_value)
diff --git a/modoboa/core/password_hashers/base.py b/modoboa/core/password_hashers/base.py
index 689ffb82a..2b2bba139 100644
--- a/modoboa/core/password_hashers/base.py
+++ b/modoboa/core/password_hashers/base.py
@@ -11,7 +11,7 @@ import string
 from random import Random
 
 from django.utils.crypto import constant_time_compare
-from django.utils.encoding import force_bytes, force_text
+from django.utils.encoding import force_bytes, force_str
 
 
 class MetaHasher(type):
@@ -65,8 +65,8 @@ class PasswordHasher(metaclass=MetaHasher):
         :rtype: str
         :return: encrypted password
         """
-        pwhash = self._b64encode(self._encrypt(force_text(clearvalue)))
-        return "%s%s" % (self.scheme, force_text(pwhash))
+        pwhash = self._b64encode(self._encrypt(force_str(clearvalue)))
+        return "%s%s" % (self.scheme, force_str(pwhash))
 
     def verify(self, clearvalue, hashed_value):
         """Verify a password against a hashed value.
diff --git a/modoboa/core/password_validation.py b/modoboa/core/password_validation.py
index 3cb944fd7..47522897d 100644
--- a/modoboa/core/password_validation.py
+++ b/modoboa/core/password_validation.py
@@ -1,7 +1,7 @@
 """Custom password validators."""
 
 from django.core.exceptions import ValidationError
-from django.utils.translation import ugettext as _, ungettext
+from django.utils.translation import gettext as _, ngettext
 
 
 class ComplexityValidator(object):
@@ -20,7 +20,7 @@ class ComplexityValidator(object):
             sum(1 for char in password if char.isdigit()) < self.digits)
         if condition:
             raise ValidationError(
-                ungettext(
+                ngettext(
                     "Password must contain at least {} digit.",
                     "Password must contain at least {} digits.",
                     self.digits
@@ -30,7 +30,7 @@ class ComplexityValidator(object):
             sum(1 for char in password if char.islower()) < self.lower)
         if condition:
             raise ValidationError(
-                ungettext(
+                ngettext(
                     "Password must contain at least {} lowercase letter.",
                     "Password must contain at least {} lowercase letters.",
                     self.lower
@@ -41,7 +41,7 @@ class ComplexityValidator(object):
             sum(1 for char in password if char.isupper()) < self.upper)
         if condition:
             raise ValidationError(
-                ungettext(
+                ngettext(
                     "Password must contain at least {} uppercase letter.",
                     "Password must contain at least {} uppercase letters.",
                     self.upper
@@ -53,7 +53,7 @@ class ComplexityValidator(object):
             self.specials)
         if condition:
             raise ValidationError(
-                ungettext(
+                ngettext(
                     "Password must contain at least {} special character.",
                     "Password must contain at least {} special characters.",
                     self.specials
diff --git a/modoboa/core/signals.py b/modoboa/core/signals.py
index 409dc2e0b..05107d396 100644
--- a/modoboa/core/signals.py
+++ b/modoboa/core/signals.py
@@ -2,36 +2,25 @@
 
 import django.dispatch
 
-account_auto_created = django.dispatch.Signal(providing_args=["user"])
-account_exported = django.dispatch.Signal(providing_args=["account"])
-account_imported = django.dispatch.Signal(
-    providing_args=["user", "account", "row"])
-account_deleted = django.dispatch.Signal(providing_args=["user"])
-account_role_changed = django.dispatch.Signal(
-    providing_args=["account", "role"])
-account_password_updated = django.dispatch.Signal(
-    providing_args=["account", "password", "created"])
-allow_password_change = django.dispatch.Signal(providing_args=["user"])
-can_create_object = django.dispatch.Signal(
-    providing_args=["context", "klass", "object_type", "count", "instance"])
-extra_account_actions = django.dispatch.Signal(providing_args=["account"])
-extra_admin_dashboard_widgets = django.dispatch.Signal(
-    providing_args=["user"])
-extra_admin_menu_entries = django.dispatch.Signal(
-    providing_args=["location", "user"])
-extra_role_permissions = django.dispatch.Signal(providing_args=["role"])
-extra_static_content = django.dispatch.Signal(
-    providing_args=["caller", "st_type", "user"])
+account_auto_created = django.dispatch.Signal() # Provides user
+account_exported = django.dispatch.Signal() # Provides account
+account_imported = django.dispatch.Signal() # Provides user, account, row
+account_deleted = django.dispatch.Signal() # Provides user
+account_role_changed = django.dispatch.Signal() # Provides account, role
+account_password_updated = django.dispatch.Signal() # Provides account password created
+allow_password_change = django.dispatch.Signal() # Provides user
+can_create_object = django.dispatch.Signal() # Provides context, klass, object_type, count, instance
+extra_account_actions = django.dispatch.Signal() # Provides account
+extra_admin_dashboard_widgets = django.dispatch.Signal() # Provides user
+extra_admin_menu_entries = django.dispatch.Signal() # Provides location, user
+extra_role_permissions = django.dispatch.Signal() # Provides role
+extra_static_content = django.dispatch.Signal() # Provides caller, st_type, user
 extra_uprefs_routes = django.dispatch.Signal()
-extra_user_menu_entries = django.dispatch.Signal(
-    providing_args=["location", "user"])
-get_announcements = django.dispatch.Signal(providing_args=["location"])
-get_top_notifications = django.dispatch.Signal(
-    providing_args=["include_all"])
-initial_data_loaded = django.dispatch.Signal(providing_args=["extname"])
+extra_user_menu_entries = django.dispatch.Signal() # Provides location, user
+get_announcements = django.dispatch.Signal() # Provides location
+get_top_notifications = django.dispatch.Signal() # Provides include_all
+initial_data_loaded = django.dispatch.Signal() # Provides extname
 register_postfix_maps = django.dispatch.Signal()
-user_can_set_role = django.dispatch.Signal(
-    providing_args=["user", "role", "account"])
-user_login = django.dispatch.Signal(
-    providing_args=["username", "password"])
+user_can_set_role = django.dispatch.Signal() # Provides user, role, account
+user_login = django.dispatch.Signal() # Provides username, password
 user_logout = django.dispatch.Signal()
diff --git a/modoboa/core/sms_backends/ovh.py b/modoboa/core/sms_backends/ovh.py
index f36f036c6..ae86a9d7b 100644
--- a/modoboa/core/sms_backends/ovh.py
+++ b/modoboa/core/sms_backends/ovh.py
@@ -4,7 +4,7 @@ import ovh
 
 from django import forms
 from django.utils.functional import cached_property
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import gettext_lazy as _
 
 from rest_framework import serializers
 
diff --git a/modoboa/core/templatetags/core_tags.py b/modoboa/core/templatetags/core_tags.py
index 04bc8ae79..3e1bee986 100644
--- a/modoboa/core/templatetags/core_tags.py
+++ b/modoboa/core/templatetags/core_tags.py
@@ -12,9 +12,9 @@ from django.contrib.sessions.models import Session
 from django.template.loader import render_to_string
 from django.urls import reverse
 from django.utils import timezone
-from django.utils.encoding import smart_text
+from django.utils.encoding import smart_str
 from django.utils.safestring import mark_safe
-from django.utils.translation import get_language, ugettext as _
+from django.utils.translation import get_language, gettext as _
 
 from .. import models
 from .. import signals
@@ -241,7 +241,7 @@ def display_messages(msgs):
     level = "info"
     for m in msgs:
         level = m.tags
-        text += smart_text(m) + "\\\n"
+        text += smart_str(m) + "\\\n"
 
     if level == "info":
         level = "success"
diff --git a/modoboa/core/tests/stupid_extension_2/urls.py b/modoboa/core/tests/stupid_extension_2/urls.py
index a7996a92b..a4098f372 100644
--- a/modoboa/core/tests/stupid_extension_2/urls.py
+++ b/modoboa/core/tests/stupid_extension_2/urls.py
@@ -1,9 +1,9 @@
 """Custom urls."""
 
-from django.conf.urls import url
+from django.urls import re_path
 
 from . import views
 
 urlpatterns = [
-    url("^$", views.test_view, name="index")
+    re_path("^$", views.test_view, name="index")
 ]
diff --git a/modoboa/core/utils.py b/modoboa/core/utils.py
index 9425581fb..9509e22ed 100644
--- a/modoboa/core/utils.py
+++ b/modoboa/core/utils.py
@@ -2,7 +2,7 @@
 
 from pkg_resources import parse_version
 
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from modoboa.core.extensions import exts_pool
 from modoboa.lib.api_client import ModoAPIClient
diff --git a/modoboa/core/views/admin.py b/modoboa/core/views/admin.py
index 881b396b9..b4681dec7 100644
--- a/modoboa/core/views/admin.py
+++ b/modoboa/core/views/admin.py
@@ -5,7 +5,7 @@ from functools import reduce
 from django.contrib.auth.decorators import login_required, user_passes_test
 from django.shortcuts import render
 from django.template.loader import render_to_string
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from modoboa.core.models import Log
 from modoboa.core.utils import check_for_updates
diff --git a/modoboa/core/views/auth.py b/modoboa/core/views/auth.py
index 29c328bf3..3057eb50d 100644
--- a/modoboa/core/views/auth.py
+++ b/modoboa/core/views/auth.py
@@ -13,7 +13,7 @@ from django.utils import translation
 from django.utils.encoding import force_bytes
 from django.utils.html import escape
 from django.utils.http import urlsafe_base64_encode
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 from django.views import generic
 from django.views.decorators.cache import never_cache
 
diff --git a/modoboa/core/views/base.py b/modoboa/core/views/base.py
index 1c5378b34..0de677140 100644
--- a/modoboa/core/views/base.py
+++ b/modoboa/core/views/base.py
@@ -2,7 +2,7 @@
 
 from django.contrib.auth import mixins as auth_mixins
 from django.urls import reverse
-from django.utils.http import is_safe_url
+from django.utils.http import url_has_allowed_host_and_scheme
 from django.views import generic
 
 from ..extensions import exts_pool
@@ -16,7 +16,7 @@ def find_nextlocation(request, user):
     nextlocation = request.POST.get("next", request.GET.get("next"))
     condition = (
         nextlocation and
-        is_safe_url(nextlocation, request.get_host())
+        url_has_allowed_host_and_scheme(nextlocation, request.get_host())
     )
     if condition:
         return nextlocation
diff --git a/modoboa/core/views/user.py b/modoboa/core/views/user.py
index a91f05379..9c5e6ae52 100644
--- a/modoboa/core/views/user.py
+++ b/modoboa/core/views/user.py
@@ -9,8 +9,8 @@ from django.conf import settings
 from django.shortcuts import render
 from django.template.loader import render_to_string
 from django.utils import translation
-from django.utils.encoding import force_text
-from django.utils.translation import ugettext as _
+from django.utils.encoding import force_str
+from django.utils.translation import gettext as _
 
 from django.contrib.auth.decorators import login_required, user_passes_test
 
@@ -52,7 +52,7 @@ def profile(request, tplname="core/user_profile.html"):
         if form.is_valid():
             form.save()
             if update_password and form.cleaned_data["confirmation"] != "":
-                request.session["password"] = force_text(encrypt(
+                request.session["password"] = force_str(encrypt(
                     form.cleaned_data["confirmation"]
                 ))
             translation.activate(request.user.language)
diff --git a/modoboa/dmarc/forms.py b/modoboa/dmarc/forms.py
index 0d4be9a44..ca374b925 100644
--- a/modoboa/dmarc/forms.py
+++ b/modoboa/dmarc/forms.py
@@ -4,7 +4,7 @@ import collections
 
 from django import forms
 from django.utils import timezone
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import gettext_lazy as _
 
 from modoboa.dmarc.api.v2 import serializers
 from modoboa.lib import form_utils
diff --git a/modoboa/dmarc/handlers.py b/modoboa/dmarc/handlers.py
index 06a4cb055..fcd89e7a7 100644
--- a/modoboa/dmarc/handlers.py
+++ b/modoboa/dmarc/handlers.py
@@ -1,7 +1,7 @@
 """Django signal handlers for modoboa_dmarc."""
 
 from django.urls import reverse
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 from django.dispatch import receiver
 
 from modoboa.admin import signals as admin_signals
diff --git a/modoboa/dmarc/lib.py b/modoboa/dmarc/lib.py
index 773d6428a..9ae04c019 100644
--- a/modoboa/dmarc/lib.py
+++ b/modoboa/dmarc/lib.py
@@ -20,8 +20,8 @@ import six
 from django.db import transaction
 from django.db.models import Q
 from django.utils import timezone
-from django.utils.encoding import smart_text
-from django.utils.translation import ugettext as _
+from django.utils.encoding import smart_str
+from django.utils.translation import gettext as _
 
 from modoboa.admin import models as admin_models
 from modoboa.parameters import tools as param_tools
@@ -57,7 +57,7 @@ def import_record(xml_node, report):
     record.spf_result = policy_evaluated.find("spf").text
     reason = policy_evaluated.find("reason")
     if reason:
-        record.reason_type = smart_text(reason.find("type").text)[:14]
+        record.reason_type = smart_str(reason.find("type").text)[:14]
         if record.reason_type not in constants.ALLOWED_REASON_TYPES:
             record.reason_type = "other"
         comment = reason.find("comment").text or ""
diff --git a/modoboa/dmarc/models.py b/modoboa/dmarc/models.py
index 4591feb41..baf57a849 100644
--- a/modoboa/dmarc/models.py
+++ b/modoboa/dmarc/models.py
@@ -1,7 +1,7 @@
 """DMARC models."""
 
 from django.db import models
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import gettext_lazy as _
 
 from modoboa.admin import models as admin_models
 
diff --git a/modoboa/dmarc/templatetags/dmarc_tags.py b/modoboa/dmarc/templatetags/dmarc_tags.py
index c313b67ae..7112ee490 100644
--- a/modoboa/dmarc/templatetags/dmarc_tags.py
+++ b/modoboa/dmarc/templatetags/dmarc_tags.py
@@ -6,7 +6,7 @@ from collections import OrderedDict
 
 from django import template
 from django.utils.safestring import mark_safe
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import gettext_lazy as _
 
 register = template.Library()
 
diff --git a/modoboa/dmarc/views.py b/modoboa/dmarc/views.py
index 68c9fdbeb..37c6ba8b4 100644
--- a/modoboa/dmarc/views.py
+++ b/modoboa/dmarc/views.py
@@ -11,7 +11,7 @@ from django.utils import timezone
 from django.views import generic
 
 from django.contrib.auth import mixins as auth_mixins
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import gettext_lazy as _
 
 from modoboa.admin import models as admin_models
 from modoboa.parameters import tools as param_tools
diff --git a/modoboa/dnstools/lib.py b/modoboa/dnstools/lib.py
index f5dac6bc0..5f92ab731 100644
--- a/modoboa/dnstools/lib.py
+++ b/modoboa/dnstools/lib.py
@@ -2,7 +2,7 @@
 
 import ipaddress
 
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from modoboa.admin import lib as admin_lib
 
diff --git a/modoboa/dnstools/models.py b/modoboa/dnstools/models.py
index e3e68ceb0..73fad5ecf 100644
--- a/modoboa/dnstools/models.py
+++ b/modoboa/dnstools/models.py
@@ -4,7 +4,7 @@ import datetime
 
 from django.db import models
 from django.utils import timezone
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from . import constants
 from . import lib
diff --git a/modoboa/dnstools/views.py b/modoboa/dnstools/views.py
index 6ce92c739..dd2297e01 100644
--- a/modoboa/dnstools/views.py
+++ b/modoboa/dnstools/views.py
@@ -1,6 +1,6 @@
 """App related views."""
 
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 from django.views import generic
 
 from django.contrib.auth import mixins as auth_mixins
diff --git a/modoboa/imap_migration/app_settings.py b/modoboa/imap_migration/app_settings.py
index c4c3a85df..d73d194da 100644
--- a/modoboa/imap_migration/app_settings.py
+++ b/modoboa/imap_migration/app_settings.py
@@ -3,7 +3,7 @@
 import collections
 
 from django import forms
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import gettext_lazy as _
 
 from modoboa.lib import form_utils
 from modoboa.parameters import forms as param_forms
diff --git a/modoboa/imap_migration/apps.py b/modoboa/imap_migration/apps.py
index d611d1da0..e3cf9fb5e 100644
--- a/modoboa/imap_migration/apps.py
+++ b/modoboa/imap_migration/apps.py
@@ -1,7 +1,7 @@
 """AppConfig for IMAP migration."""
 
 from django.apps import AppConfig
-from django.utils.translation import ugettext_lazy
+from django.utils.translation import gettext_lazy
 
 
 def load_imapmigration_settings():
@@ -15,9 +15,9 @@ def load_imapmigration_settings():
     from .api.v2 import serializers
 
     param_tools.registry.add(
-        "global", app_settings.ParametersForm, ugettext_lazy("IMAP Migration"))
+        "global", app_settings.ParametersForm, gettext_lazy("IMAP Migration"))
     param_tools.registry.add2(
-        "global", "imap_migration", ugettext_lazy("IMAP Migration"),
+        "global", "imap_migration", gettext_lazy("IMAP Migration"),
         app_settings.IMAP_MIGRATION_PARAMETERS_STRUCT,
         serializers.IMAPMigrationSettingsSerializer,
         True)
diff --git a/modoboa/imap_migration/auth_backends.py b/modoboa/imap_migration/auth_backends.py
index c1ecf79f3..ac6afe3b7 100644
--- a/modoboa/imap_migration/auth_backends.py
+++ b/modoboa/imap_migration/auth_backends.py
@@ -5,7 +5,7 @@ import socket
 import ssl
 
 from django.utils.encoding import smart_bytes, smart_str
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from modoboa.core import models as core_models
 from modoboa.lib import email_utils
diff --git a/modoboa/imap_migration/checks.py b/modoboa/imap_migration/checks.py
index 6f20e160b..9ace9a5ea 100644
--- a/modoboa/imap_migration/checks.py
+++ b/modoboa/imap_migration/checks.py
@@ -2,7 +2,7 @@
 
 from django.core.checks import Warning, register
 
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from modoboa.core import models as core_models
 
diff --git a/modoboa/ldapsync/lib.py b/modoboa/ldapsync/lib.py
index 4d4b7b269..ae2c87120 100644
--- a/modoboa/ldapsync/lib.py
+++ b/modoboa/ldapsync/lib.py
@@ -5,7 +5,7 @@ import ldap.modlist as modlist
 
 from django.conf import settings
 from django.utils.encoding import force_bytes, force_str
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from modoboa.core import models as core_models
 from modoboa.lib.email_utils import split_mailbox
diff --git a/modoboa/lib/api_client.py b/modoboa/lib/api_client.py
index a63c80012..e47b38cf1 100644
--- a/modoboa/lib/api_client.py
+++ b/modoboa/lib/api_client.py
@@ -7,7 +7,7 @@ import pkg_resources
 import requests
 from requests.exceptions import RequestException
 
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 logger = logging.getLogger("modoboa.admin")
 
diff --git a/modoboa/lib/cryptutils.py b/modoboa/lib/cryptutils.py
index d413af9b4..19d3f004b 100644
--- a/modoboa/lib/cryptutils.py
+++ b/modoboa/lib/cryptutils.py
@@ -11,7 +11,7 @@ from cryptography.hazmat.primitives.hashes import SHA1
 
 from django.conf import settings
 from django.utils.crypto import get_random_string
-from django.utils.encoding import smart_bytes, smart_text
+from django.utils.encoding import smart_bytes, smart_str
 
 
 def random_key(length=16):
@@ -34,12 +34,12 @@ def _get_fernet():
 
 def encrypt(clear_value):
     """Encrypt a value using secret_key."""
-    return smart_text(_get_fernet().encrypt(smart_bytes(clear_value)))
+    return smart_str(_get_fernet().encrypt(smart_bytes(clear_value)))
 
 
 def decrypt(encrypted_value):
     """Decrypt a value using secret_key."""
-    return smart_text(_get_fernet().decrypt(smart_bytes(encrypted_value)))
+    return smart_str(_get_fernet().decrypt(smart_bytes(encrypted_value)))
 
 
 def get_password(request):
diff --git a/modoboa/lib/db_utils.py b/modoboa/lib/db_utils.py
index 569bc8e9f..03b279f80 100644
--- a/modoboa/lib/db_utils.py
+++ b/modoboa/lib/db_utils.py
@@ -1,6 +1,6 @@
 from django.conf import settings
 from django.db import connection
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from modoboa.lib.exceptions import InternalError
 
diff --git a/modoboa/lib/email_utils.py b/modoboa/lib/email_utils.py
index d3b30b76e..ffb102ec3 100644
--- a/modoboa/lib/email_utils.py
+++ b/modoboa/lib/email_utils.py
@@ -13,9 +13,9 @@ from lxml.html.clean import Cleaner
 
 from django.core.mail import EmailMessage
 from django.template.loader import render_to_string
-from django.utils.encoding import smart_str, smart_text
+from django.utils.encoding import smart_str, smart_str
 from django.utils.html import conditional_escape, escape
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from modoboa.core import models as core_models
 from modoboa.lib import u2u_decode
@@ -130,7 +130,7 @@ class Email(object):
                 if not len(value):
                     continue
                 if encoding:
-                    value = smart_text(value, encoding=encoding)
+                    value = smart_str(value, encoding=encoding)
                 elif isinstance(value, bytes):
                     # SMTPUTF8 fallback (most of the time)
                     # Address contains non ASCII chars but is not RFC2047
@@ -229,7 +229,7 @@ class Email(object):
             _RE_REMOVE_EXTRA_WHITESPACE.sub("\n\n", content).strip()
         )
         mail_text = escape(mail_text)
-        return smart_text(mail_text)
+        return smart_str(mail_text)
 
     def _post_process_html(self, content):
         html = lxml.html.fromstring(content)
@@ -253,7 +253,7 @@ class Email(object):
         )
         mail_text = lxml.html.tostring(
             cleaner.clean_html(html), encoding="unicode")
-        return smart_text(mail_text)
+        return smart_str(mail_text)
 
     def _map_cid(self, url):
         if url.startswith("cid:"):
diff --git a/modoboa/lib/exceptions.py b/modoboa/lib/exceptions.py
index 2e740597d..05f8e0d2d 100644
--- a/modoboa/lib/exceptions.py
+++ b/modoboa/lib/exceptions.py
@@ -4,7 +4,7 @@
 
 """
 
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 
 class ModoboaException(Exception):
diff --git a/modoboa/lib/fields.py b/modoboa/lib/fields.py
index c5e81ff11..19941473c 100644
--- a/modoboa/lib/fields.py
+++ b/modoboa/lib/fields.py
@@ -1,7 +1,7 @@
 """Custom form fields."""
 
 from django import forms
-from django.utils.translation import ugettext_lazy
+from django.utils.translation import gettext_lazy
 
 from rest_framework import serializers
 
@@ -12,7 +12,7 @@ class DomainNameField(forms.fields.CharField):
     """A subclass of CharField that only accepts a valid domain name."""
 
     default_error_messages = {
-        "invalid": ugettext_lazy("Enter a valid domain name")
+        "invalid": gettext_lazy("Enter a valid domain name")
     }
 
     default_validators = [validators.validate_hostname]
@@ -41,7 +41,7 @@ class DRFEmailFieldUTF8(serializers.CharField):
     """Custom DRF email field to support UTF8."""
 
     default_error_messages = {
-        "invalid": ugettext_lazy("Enter a valid email address.")
+        "invalid": gettext_lazy("Enter a valid email address.")
     }
 
     def __init__(self, **kwargs):
@@ -55,7 +55,7 @@ class DRFEmailFieldUTF8AndEmptyUser(serializers.CharField):
     """Custom DRF email field to support UTF8 and empty local part."""
 
     default_error_messages = {
-        "invalid": ugettext_lazy("Enter a valid email address.")
+        "invalid": gettext_lazy("Enter a valid email address.")
     }
 
     def __init__(self, **kwargs):
diff --git a/modoboa/lib/form_utils.py b/modoboa/lib/form_utils.py
index 771840bfe..1118fc8f0 100644
--- a/modoboa/lib/form_utils.py
+++ b/modoboa/lib/form_utils.py
@@ -9,7 +9,7 @@ from django.forms.fields import Field
 from django.forms.widgets import RadioSelect
 from django.shortcuts import render
 from django.utils.encoding import force_str
-from django.utils.translation import ugettext as _, ugettext_lazy
+from django.utils.translation import gettext as _, gettext_lazy
 
 from modoboa.lib.exceptions import BadRequest
 from modoboa.lib.web_utils import render_to_json_response
@@ -393,8 +393,8 @@ class YesNoField(TypedChoiceField):
         """Constructor."""
         kwargs.update({
             "choices": (
-                (True, ugettext_lazy("Yes")),
-                (False, ugettext_lazy("No"))
+                (True, gettext_lazy("Yes")),
+                (False, gettext_lazy("No"))
             ),
             "widget": HorizontalRadioSelect(),
             "coerce": lambda x: x == "True"
diff --git a/modoboa/lib/ldap_utils.py b/modoboa/lib/ldap_utils.py
index c981c25ab..cbadc8e1e 100644
--- a/modoboa/lib/ldap_utils.py
+++ b/modoboa/lib/ldap_utils.py
@@ -35,7 +35,7 @@ import ldap
 
 from django.conf import settings
 from django.utils.encoding import force_bytes, force_str
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from modoboa.core.password_hashers import get_password_hasher
 from modoboa.lib.exceptions import InternalError
diff --git a/modoboa/lib/middleware.py b/modoboa/lib/middleware.py
index 5262af691..4d02b7f15 100644
--- a/modoboa/lib/middleware.py
+++ b/modoboa/lib/middleware.py
@@ -2,7 +2,7 @@
 
 from django.http import HttpResponseRedirect
 from django.utils.deprecation import MiddlewareMixin
-from django.utils.encoding import smart_text
+from django.utils.encoding import smart_str
 
 from modoboa.lib import signals as lib_signals
 from modoboa.lib.exceptions import ModoboaException
@@ -11,10 +11,14 @@ from modoboa.lib.web_utils import (
 )
 
 
+def is_ajax(request):
+    return request.META.get('HTTP_X_REQUESTED_WITH') == 'XMLHttpRequest'
+
+
 class AjaxLoginRedirect(MiddlewareMixin):
 
     def process_response(self, request, response):
-        if request.is_ajax():
+        if is_ajax(request):
             if isinstance(response, HttpResponseRedirect):
                 response.status_code = 278
         return response
@@ -27,17 +31,17 @@ class CommonExceptionCatcher(MiddlewareMixin):
         if not isinstance(exception, ModoboaException):
             return None
 
-        if request.is_ajax() or "/api/" in request.path:
+        if is_ajax(request) or "/api/" in request.path:
             if exception.http_code is None:
                 return ajax_response(
-                    request, status="ko", respmsg=smart_text(exception),
+                    request, status="ko", respmsg=smart_str(exception),
                     norefresh=True
                 )
             return render_to_json_response(
-                smart_text(exception), status=exception.http_code
+                smart_str(exception), status=exception.http_code
             )
         return _render_error(
-            request, user_context={"error": smart_text(exception)}
+            request, user_context={"error": smart_str(exception)}
         )
 
 
diff --git a/modoboa/lib/sysutils.py b/modoboa/lib/sysutils.py
index d290a04a7..6877b3fd0 100644
--- a/modoboa/lib/sysutils.py
+++ b/modoboa/lib/sysutils.py
@@ -10,7 +10,7 @@ import re
 import subprocess
 
 from django.conf import settings
-from django.utils.encoding import force_text
+from django.utils.encoding import force_str
 
 
 def exec_cmd(cmd, sudo_user=None, pinput=None, capture_output=True, **kwargs):
@@ -59,7 +59,7 @@ def doveadm_cmd(params, pinput=None, capture_output=True, **kwargs):
     dpath = None
     code, output = exec_cmd("which doveadm")
     if not code:
-        dpath = force_text(output).strip()
+        dpath = force_str(output).strip()
     else:
         known_paths = getattr(
             settings, "DOVEADM_LOOKUP_PATH",
diff --git a/modoboa/lib/templatetags/form_tags.py b/modoboa/lib/templatetags/form_tags.py
index fad4637bb..869f9fdd5 100644
--- a/modoboa/lib/templatetags/form_tags.py
+++ b/modoboa/lib/templatetags/form_tags.py
@@ -4,7 +4,7 @@ Form rendering tags.
 
 from django import forms, template
 from django.template.loader import render_to_string
-from django.utils.encoding import smart_text
+from django.utils.encoding import smart_str
 from django.utils.safestring import mark_safe
 
 from modoboa.lib.form_utils import SeparatorField
@@ -43,7 +43,7 @@ def render_field(
     from modoboa.core.templatetags.core_tags import visirule
 
     if isinstance(field.field, SeparatorField):
-        return "<h5%s>%s</h5>" % (visirule(field), smart_text(field.label))
+        return "<h5%s>%s</h5>" % (visirule(field), smart_str(field.label))
     configure_field_classes(field)
     context = {
         "field": field, "help_display_mode": help_display_mode,
diff --git a/modoboa/lib/templatetags/lib_tags.py b/modoboa/lib/templatetags/lib_tags.py
index 22cf15146..2f72b088a 100644
--- a/modoboa/lib/templatetags/lib_tags.py
+++ b/modoboa/lib/templatetags/lib_tags.py
@@ -5,7 +5,7 @@ from datetime import datetime
 from django import template
 from django.template import Context, Template
 from django.utils.safestring import mark_safe
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from modoboa.core import signals as core_signals
 
diff --git a/modoboa/lib/tests/test_email_utils.py b/modoboa/lib/tests/test_email_utils.py
index b64007d3b..405cec905 100644
--- a/modoboa/lib/tests/test_email_utils.py
+++ b/modoboa/lib/tests/test_email_utils.py
@@ -3,7 +3,7 @@
 import os
 
 from django.test import SimpleTestCase
-from django.utils.encoding import smart_bytes, smart_text
+from django.utils.encoding import smart_bytes, smart_str
 
 from ..email_utils import (
     Email, prepare_addresses, split_address, split_local_part
@@ -44,7 +44,7 @@ class EmailTests(SimpleTestCase):
 
         with open(message_path, "rb") as fp:
             # output should always be unicode (py2) or str (py3)
-            mail_text = smart_text(fp.read())
+            mail_text = smart_str(fp.read())
 
         return mail_text
 
diff --git a/modoboa/lib/u2u_decode.py b/modoboa/lib/u2u_decode.py
index 34a89e917..c7d3c5cef 100644
--- a/modoboa/lib/u2u_decode.py
+++ b/modoboa/lib/u2u_decode.py
@@ -9,7 +9,7 @@ import re
 from email.header import decode_header, make_header
 from email.utils import parseaddr
 
-from django.utils.encoding import smart_text
+from django.utils.encoding import smart_str
 
 # check spaces between encoded_words (and strip them)
 sre = re.compile(r"\?=[ \t]+=\?")
@@ -40,7 +40,7 @@ def decode_mime(m):
     """Substitute matching encoded_word with unicode equiv."""
     h = decode_header(clean_spaces(m))
     try:
-        u = smart_text(make_header(h))
+        u = smart_str(make_header(h))
     except (LookupError, UnicodeDecodeError):
         return m.group(0)
     return u
diff --git a/modoboa/lib/validators.py b/modoboa/lib/validators.py
index fd7e4b91f..645e18dfa 100644
--- a/modoboa/lib/validators.py
+++ b/modoboa/lib/validators.py
@@ -4,14 +4,14 @@ import re
 
 from django.core.exceptions import ValidationError
 from django.core.validators import EmailValidator, URLValidator
-from django.utils.translation import ugettext_lazy
+from django.utils.translation import gettext_lazy
 
 
 class HostnameValidator(object):
 
     """Validator for fqdn."""
 
-    message = ugettext_lazy("Enter a valid domain name")
+    message = gettext_lazy("Enter a valid domain name")
     code = "invalid"
     regex = re.compile(URLValidator.host_re)
 
diff --git a/modoboa/limits/app_settings.py b/modoboa/limits/app_settings.py
index f4fe0f686..001a0ccf9 100644
--- a/modoboa/limits/app_settings.py
+++ b/modoboa/limits/app_settings.py
@@ -3,7 +3,7 @@
 import collections
 
 from django import forms
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import gettext_lazy as _
 
 from modoboa.lib.form_utils import SeparatorField, YesNoField
 from modoboa.parameters import forms as param_forms
diff --git a/modoboa/limits/apps.py b/modoboa/limits/apps.py
index a2f32805b..2f204b0e3 100644
--- a/modoboa/limits/apps.py
+++ b/modoboa/limits/apps.py
@@ -1,7 +1,7 @@
 """App config for limits."""
 
 from django.apps import AppConfig
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 
 def load_limits_settings():
diff --git a/modoboa/limits/constants.py b/modoboa/limits/constants.py
index c916b2b93..970d9eef7 100644
--- a/modoboa/limits/constants.py
+++ b/modoboa/limits/constants.py
@@ -2,7 +2,7 @@
 
 import collections
 
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import gettext_lazy as _
 
 DEFAULT_USER_LIMITS = collections.OrderedDict((
     ("domains", {
diff --git a/modoboa/limits/forms.py b/modoboa/limits/forms.py
index ac6842505..ddaf69f1d 100644
--- a/modoboa/limits/forms.py
+++ b/modoboa/limits/forms.py
@@ -1,7 +1,7 @@
 """Custom forms."""
 
 from django import forms
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from modoboa.lib.permissions import get_object_owner
 from . import utils
diff --git a/modoboa/limits/handlers.py b/modoboa/limits/handlers.py
index d595f8f3d..a2992db20 100644
--- a/modoboa/limits/handlers.py
+++ b/modoboa/limits/handlers.py
@@ -4,7 +4,7 @@ from django.contrib.contenttypes.models import ContentType
 from django.db.models import signals
 from django.dispatch import receiver
 from django.template.loader import render_to_string
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from modoboa.admin import models as admin_models, signals as admin_signals
 from modoboa.core import models as core_models, signals as core_signals
diff --git a/modoboa/limits/lib.py b/modoboa/limits/lib.py
index 7da7b97e8..f186bc07f 100644
--- a/modoboa/limits/lib.py
+++ b/modoboa/limits/lib.py
@@ -4,7 +4,7 @@
 
 """
 
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from modoboa.lib.exceptions import ModoboaException
 
diff --git a/modoboa/limits/models.py b/modoboa/limits/models.py
index 65445c342..2f12d8285 100644
--- a/modoboa/limits/models.py
+++ b/modoboa/limits/models.py
@@ -3,7 +3,7 @@
 from django.conf import settings
 from django.db import models
 from django.utils.functional import cached_property
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from modoboa.core import models as core_models
 from . import lib, utils
diff --git a/modoboa/maillog/api/v2/serializers.py b/modoboa/maillog/api/v2/serializers.py
index f6c204d76..3d45c627d 100644
--- a/modoboa/maillog/api/v2/serializers.py
+++ b/modoboa/maillog/api/v2/serializers.py
@@ -1,6 +1,6 @@
 """App. related serializers."""
 
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from rest_framework import serializers
 
diff --git a/modoboa/maillog/forms.py b/modoboa/maillog/forms.py
index 2d38ff2f1..240546199 100644
--- a/modoboa/maillog/forms.py
+++ b/modoboa/maillog/forms.py
@@ -5,7 +5,7 @@ import rrdtool
 from pkg_resources import parse_version
 
 from django.conf import settings
-from django.utils.translation import ugettext_lazy
+from django.utils.translation import gettext_lazy
 from django import forms
 
 from modoboa.lib import form_utils
@@ -17,27 +17,27 @@ class ParametersForm(param_forms.AdminParametersForm):
 
     app = "maillog"
 
-    general_sep = form_utils.SeparatorField(label=ugettext_lazy("General"))
+    general_sep = form_utils.SeparatorField(label=gettext_lazy("General"))
 
     logfile = forms.CharField(
-        label=ugettext_lazy("Path to the log file"),
+        label=gettext_lazy("Path to the log file"),
         initial="/var/log/mail.log",
-        help_text=ugettext_lazy("Path to log file used to collect statistics"),
+        help_text=gettext_lazy("Path to log file used to collect statistics"),
         widget=forms.TextInput(attrs={"class": "form-control"})
     )
 
     rrd_rootdir = forms.CharField(
-        label=ugettext_lazy("Directory to store RRD files"),
+        label=gettext_lazy("Directory to store RRD files"),
         initial="/tmp/modoboa",
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Path to directory where RRD files are stored"),
         widget=forms.TextInput(attrs={"class": "form-control"})
     )
 
     greylist = form_utils.YesNoField(
-        label=ugettext_lazy("Show greylisted messages"),
+        label=gettext_lazy("Show greylisted messages"),
         initial=False,
-        help_text=ugettext_lazy(
+        help_text=gettext_lazy(
             "Differentiate between hard and soft rejects (greylisting)")
     )
 
@@ -56,4 +56,4 @@ def load_settings():
     from modoboa.parameters import tools as param_tools
 
     param_tools.registry.add(
-        "global", ParametersForm, ugettext_lazy("Statistics"))
+        "global", ParametersForm, gettext_lazy("Statistics"))
diff --git a/modoboa/maillog/graphics.py b/modoboa/maillog/graphics.py
index e228ed0f7..2bac4c098 100644
--- a/modoboa/maillog/graphics.py
+++ b/modoboa/maillog/graphics.py
@@ -7,8 +7,8 @@ from itertools import chain
 import os
 
 from django.conf import settings
-from django.utils.encoding import smart_bytes, smart_text
-from django.utils.translation import ugettext as _, ugettext_lazy
+from django.utils.encoding import smart_bytes, smart_str
+from django.utils.translation import gettext as _, gettext_lazy
 
 from modoboa.admin import models as admin_models
 from modoboa.lib import exceptions
@@ -91,7 +91,7 @@ class Graphic:
         if dpath is None:
             raise exceptions.InternalError(
                 _("Failed to locate rrdtool binary."))
-        return smart_text(dpath)
+        return smart_str(dpath)
 
     def export(self, rrdfile, start, end):
         """Export data to JSON using rrdtool."""
@@ -167,22 +167,22 @@ class GraphicSet(object):
 class AverageTraffic(Graphic):
     """Average traffic."""
 
-    title = ugettext_lazy('Average traffic (msgs/min)')
+    title = gettext_lazy('Average traffic (msgs/min)')
 
     # Curve definitions
-    sent = Curve("sent", "lawngreen", ugettext_lazy("sent messages"))
-    recv = Curve("recv", "steelblue", ugettext_lazy("received messages"))
-    bounced = Curve("bounced", "yellow", ugettext_lazy("bounced messages"))
-    reject = Curve("reject", "tomato", ugettext_lazy("rejected messages"))
-    virus = Curve("virus", "orange", ugettext_lazy("virus messages"))
-    spam = Curve("spam", "silver", ugettext_lazy("spam messages"))
+    sent = Curve("sent", "lawngreen", gettext_lazy("sent messages"))
+    recv = Curve("recv", "steelblue", gettext_lazy("received messages"))
+    bounced = Curve("bounced", "yellow", gettext_lazy("bounced messages"))
+    reject = Curve("reject", "tomato", gettext_lazy("rejected messages"))
+    virus = Curve("virus", "orange", gettext_lazy("virus messages"))
+    spam = Curve("spam", "silver", gettext_lazy("spam messages"))
 
     order = ["reject", "bounced", "recv", "sent", "virus", "spam"]
 
     def __init__(self, greylist=False):
         if greylist:
             self.greylist = Curve(
-                "greylist", "dimgrey", ugettext_lazy("greylisted messages"))
+                "greylist", "dimgrey", gettext_lazy("greylisted messages"))
             self.order = [
                 "reject", "greylist", "bounced", "recv", "sent", "virus",
                 "spam"
@@ -193,12 +193,12 @@ class AverageTraffic(Graphic):
 class AverageTrafficSize(Graphic):
     """Average traffic size."""
 
-    title = ugettext_lazy('Average normal traffic size (bytes/min)')
+    title = gettext_lazy('Average normal traffic size (bytes/min)')
 
     # Curve definitions
-    size_recv = Curve("size_recv", "orange", ugettext_lazy("received size"))
+    size_recv = Curve("size_recv", "orange", gettext_lazy("received size"))
     size_sent = Curve(
-        "size_sent", "mediumturquoise", ugettext_lazy("sent size")
+        "size_sent", "mediumturquoise", gettext_lazy("sent size")
     )
 
 
@@ -206,7 +206,7 @@ class MailTraffic(GraphicSet):
     """Mail traffic graphic set."""
 
     domain_selector = True
-    title = ugettext_lazy("Mail traffic")
+    title = gettext_lazy("Mail traffic")
     _graphics = [AverageTraffic, AverageTrafficSize]
 
     def __init__(self, greylist=False):
@@ -250,15 +250,15 @@ class MailTraffic(GraphicSet):
 class AccountCreationGraphic(Graphic):
     """Account creation over time."""
 
-    title = ugettext_lazy("Average account creation (account/hour)")
+    title = gettext_lazy("Average account creation (account/hour)")
 
     accounts = Curve(
-        "new_accounts", "steelblue", ugettext_lazy("New accounts"))
+        "new_accounts", "steelblue", gettext_lazy("New accounts"))
 
 
 class AccountGraphicSet(GraphicSet):
     """A graphic set for accounts."""
 
     file_name = "new_accounts"
-    title = ugettext_lazy("Accounts")
+    title = gettext_lazy("Accounts")
     _graphics = [AccountCreationGraphic]
diff --git a/modoboa/maillog/handlers.py b/modoboa/maillog/handlers.py
index 5d820954a..99ff0c906 100644
--- a/modoboa/maillog/handlers.py
+++ b/modoboa/maillog/handlers.py
@@ -2,7 +2,7 @@
 
 from django.urls import reverse
 from django.dispatch import receiver
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from modoboa.admin import signals as admin_signals
 from modoboa.core import signals as core_signals
diff --git a/modoboa/maillog/signals.py b/modoboa/maillog/signals.py
index 59b2c7ae4..28b476cae 100644
--- a/modoboa/maillog/signals.py
+++ b/modoboa/maillog/signals.py
@@ -2,4 +2,4 @@
 
 import django.dispatch
 
-get_graph_sets = django.dispatch.Signal(providing_args=["user"])
+get_graph_sets = django.dispatch.Signal() # Provides user
diff --git a/modoboa/maillog/views.py b/modoboa/maillog/views.py
index 159464861..b2dcedb0e 100644
--- a/modoboa/maillog/views.py
+++ b/modoboa/maillog/views.py
@@ -6,7 +6,7 @@ import re
 import time
 
 from django.shortcuts import render
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 from django.contrib.auth.decorators import (
     login_required, user_passes_test, permission_required
 )
diff --git a/modoboa/pdfcredentials/api/v2/serializers.py b/modoboa/pdfcredentials/api/v2/serializers.py
index ffb8dcf4b..2832f8ca5 100644
--- a/modoboa/pdfcredentials/api/v2/serializers.py
+++ b/modoboa/pdfcredentials/api/v2/serializers.py
@@ -2,7 +2,7 @@
 
 import os
 
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import gettext_lazy as _
 
 from rest_framework import serializers, status
 from rest_framework.exceptions import PermissionDenied, APIException
diff --git a/modoboa/pdfcredentials/api/v2/views.py b/modoboa/pdfcredentials/api/v2/views.py
index 5d2345fce..d7ddc1f03 100644
--- a/modoboa/pdfcredentials/api/v2/views.py
+++ b/modoboa/pdfcredentials/api/v2/views.py
@@ -2,7 +2,7 @@
 
 import os
 
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 from django.http import HttpResponse
 
 from rest_framework import permissions
diff --git a/modoboa/pdfcredentials/app_settings.py b/modoboa/pdfcredentials/app_settings.py
index d0055c055..54ec06f10 100644
--- a/modoboa/pdfcredentials/app_settings.py
+++ b/modoboa/pdfcredentials/app_settings.py
@@ -5,7 +5,7 @@ import collections
 from django import forms
 from django.conf import settings
 from django.utils.functional import cached_property
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import gettext_lazy as _
 
 from django.contrib.sites import models as sites_models
 
diff --git a/modoboa/pdfcredentials/apps.py b/modoboa/pdfcredentials/apps.py
index 2342e98af..cb47c6bb0 100644
--- a/modoboa/pdfcredentials/apps.py
+++ b/modoboa/pdfcredentials/apps.py
@@ -2,7 +2,7 @@
 
 from django.apps import AppConfig
 
-from django.utils.translation import ugettext_lazy
+from django.utils.translation import gettext_lazy
 
 
 def load_pdfcredential_settings():
@@ -16,9 +16,9 @@ def load_pdfcredential_settings():
     from .api.v2 import serializers
 
     param_tools.registry.add(
-        "global", app_settings.ParametersForm, ugettext_lazy("PDF credentials"))
+        "global", app_settings.ParametersForm, gettext_lazy("PDF credentials"))
     param_tools.registry.add2(
-        "global", "pdfcredentials", ugettext_lazy("PDF Credentials"),
+        "global", "pdfcredentials", gettext_lazy("PDF Credentials"),
         app_settings.PDF_CREDENTIALS_PARAMETERS_STRUCT,
         serializers.PDFCredentialsSettingsSerializer,
         True)
diff --git a/modoboa/pdfcredentials/constants.py b/modoboa/pdfcredentials/constants.py
index c0a407a9c..0dd979ccc 100644
--- a/modoboa/pdfcredentials/constants.py
+++ b/modoboa/pdfcredentials/constants.py
@@ -1,10 +1,10 @@
 """PDF credentials constants."""
 
-from django.utils.translation import ugettext_lazy
+from django.utils.translation import gettext_lazy
 
 
 CONNECTION_SECURITY_MODES = [
-    ("none", ugettext_lazy("None")),
+    ("none", gettext_lazy("None")),
     ("starttls", "STARTTLS"),
     ("tls", "TLS")
 ]
diff --git a/modoboa/pdfcredentials/documents.py b/modoboa/pdfcredentials/documents.py
index adaf9b572..edc2bc973 100644
--- a/modoboa/pdfcredentials/documents.py
+++ b/modoboa/pdfcredentials/documents.py
@@ -13,7 +13,7 @@ from reportlab.platypus import (
 )
 from reportlab.lib.styles import getSampleStyleSheet, ParagraphStyle
 
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from modoboa.parameters import tools as param_tools
 
diff --git a/modoboa/pdfcredentials/handlers.py b/modoboa/pdfcredentials/handlers.py
index c364e98e7..ba8e1ae53 100644
--- a/modoboa/pdfcredentials/handlers.py
+++ b/modoboa/pdfcredentials/handlers.py
@@ -5,7 +5,7 @@ import os
 from django.urls import reverse
 from django.db.models import signals
 from django.dispatch import receiver
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from modoboa.admin import signals as admin_signals
 from modoboa.core import models as core_models
diff --git a/modoboa/pdfcredentials/lib.py b/modoboa/pdfcredentials/lib.py
index 2fdeeb8fc..363703855 100644
--- a/modoboa/pdfcredentials/lib.py
+++ b/modoboa/pdfcredentials/lib.py
@@ -11,7 +11,7 @@ from urllib.parse import quote
 
 from django.conf import settings
 from django.utils.encoding import force_bytes, smart_bytes
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from modoboa.lib.exceptions import InternalError
 from modoboa.parameters import tools as param_tools
diff --git a/modoboa/pdfcredentials/views.py b/modoboa/pdfcredentials/views.py
index 7fe1b7d8e..d4485c85b 100644
--- a/modoboa/pdfcredentials/views.py
+++ b/modoboa/pdfcredentials/views.py
@@ -3,7 +3,7 @@
 import os
 
 from django.http import HttpResponse
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from django.contrib.auth.decorators import (
     login_required, permission_required
diff --git a/modoboa/policyd/core.py b/modoboa/policyd/core.py
index f598271b2..58b1bfedf 100644
--- a/modoboa/policyd/core.py
+++ b/modoboa/policyd/core.py
@@ -15,7 +15,7 @@ from django.db import connections
 from django.template.loader import render_to_string
 from django.utils import timezone
 from django.utils import translation
-from django.utils.translation import ugettext as _, ugettext_lazy
+from django.utils.translation import gettext as _, gettext_lazy
 
 from modoboa.admin import constants as admin_constants
 from modoboa.admin import models as admin_models
@@ -102,8 +102,8 @@ def create_alarm(ltype, name):
 async def notify_limit_reached(ltype, name):
     """Send a notification to super admins about item."""
     ltype_translations = {
-        "account": ugettext_lazy("account"),
-        "domain": ugettext_lazy("domain")
+        "account": gettext_lazy("account"),
+        "domain": gettext_lazy("domain")
     }
     # We're going to execute sync code so we need an executor
     executor = concurrent.futures.ThreadPoolExecutor(max_workers=3)
diff --git a/modoboa/relaydomains/api/v1/serializers.py b/modoboa/relaydomains/api/v1/serializers.py
index 26cfbede1..c4eab23a7 100644
--- a/modoboa/relaydomains/api/v1/serializers.py
+++ b/modoboa/relaydomains/api/v1/serializers.py
@@ -2,7 +2,7 @@
 
 import json
 
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from rest_framework import serializers
 
diff --git a/modoboa/relaydomains/handlers.py b/modoboa/relaydomains/handlers.py
index 14102bdd4..a901052a4 100644
--- a/modoboa/relaydomains/handlers.py
+++ b/modoboa/relaydomains/handlers.py
@@ -2,7 +2,7 @@
 
 from django.db.models import signals
 from django.dispatch import receiver
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from modoboa.admin import models as admin_models, signals as admin_signals
 from modoboa.core import signals as core_signals
diff --git a/modoboa/relaydomains/lib.py b/modoboa/relaydomains/lib.py
index 41d28eb40..aa4f816a8 100644
--- a/modoboa/relaydomains/lib.py
+++ b/modoboa/relaydomains/lib.py
@@ -1,6 +1,6 @@
 """Internal library."""
 
-from django.utils.translation import ugettext as _
+from django.utils.translation import gettext as _
 
 from modoboa.admin import models as admin_models
 from modoboa.lib.exceptions import BadRequest
diff --git a/modoboa/relaydomains/transport.py b/modoboa/relaydomains/transport.py
index 8c1c77aeb..a357f2b52 100644
--- a/modoboa/relaydomains/transport.py
+++ b/modoboa/relaydomains/transport.py
@@ -1,6 +1,6 @@
 """Transport backend definition."""
 
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import gettext_lazy as _
 
 from modoboa.transport import backends
 
diff --git a/modoboa/transport/backends.py b/modoboa/transport/backends.py
index b6923b16d..ab18bfaeb 100644
--- a/modoboa/transport/backends.py
+++ b/modoboa/transport/backends.py
@@ -2,7 +2,7 @@
 
 from django import forms
 from django.core import validators
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import gettext_lazy as _
 
 from modoboa.lib import validators as lib_validators
 
diff --git a/modoboa/transport/models.py b/modoboa/transport/models.py
index e92166f21..6356293b7 100644
--- a/modoboa/transport/models.py
+++ b/modoboa/transport/models.py
@@ -4,7 +4,7 @@ import jsonfield
 from reversion import revisions as reversion
 
 from django.db import models
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import gettext_lazy as _
 
 from . import backends
 
diff --git a/requirements.txt b/requirements.txt
index 68564dcdf..6e6ef39b4 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,4 +1,4 @@
-django<4.0
+django>4.0,<5.0
 django-ckeditor==6.3.0
 django-phonenumber-field[phonenumbers]==7.1.0
 django-reversion==5.0.4