diff --git a/doc/manual_installation/dovecot.rst b/doc/manual_installation/dovecot.rst
index 60fdaa319..9c759faf1 100644
--- a/doc/manual_installation/dovecot.rst
+++ b/doc/manual_installation/dovecot.rst
@@ -147,11 +147,11 @@ MySQL users
 
   default_pass_scheme = CRYPT
 
-  password_query = SELECT email AS user, password FROM core_user WHERE email='%u' and is_active=1
+  password_query = SELECT email AS user, password FROM core_user WHERE email='%Lu' and is_active=1
 
-  user_query = SELECT '<mailboxes storage directory>/%Ld/%Ln' AS home, <uid> as uid, <gid> as gid, concat('*:bytes=', mb.quota, 'M') AS quota_rule FROM admin_mailbox mb INNER JOIN admin_domain dom ON mb.domain_id=dom.id WHERE mb.address='%Ln' AND dom.name='%Ld'
+   user_query = SELECT '<mailboxes storage directory>/%Ld/%Ln' AS home, <uid> as uid, <gid> as gid, concat('*:bytes=', mb.quota, 'M') AS quota_rule FROM admin_mailbox mb INNER JOIN admin_domain dom ON mb.domain_id=dom.id WHERE mb.address='%Ln' AND dom.name='%Ld'
 
-  iterate_query = SELECT email AS username FROM core_user WHERE email<>''
+  iterate_query = SELECT email AS user FROM core_user
 
 .. _dovecot_pg_queries:
 
@@ -166,11 +166,11 @@ PostgreSQL users
 
   default_pass_scheme = CRYPT
 
-  password_query = SELECT email AS user, password FROM core_user WHERE email='%u' and is_active
+  password_query = SELECT email AS user, password FROM core_user u INNER JOIN admin_mailbox mb ON u.id=mb.user_id INNER JOIN admin_domain dom ON mb.domain_id=dom.id WHERE u.email='%Lu' AND u.is_active AND dom.enabled
 
   user_query = SELECT '<mailboxes storage directory>/%Ld/%Ln' AS home, <uid> as uid, <gid> as gid, '*:bytes=' || mb.quota || 'M' AS quota_rule FROM admin_mailbox mb INNER JOIN admin_domain dom ON mb.domain_id=dom.id WHERE mb.address='%Ln' AND dom.name='%Ld'
 
-  iterate_query = SELECT email AS username FROM core_user WHERE email<>''
+  iterate_query = SELECT email AS user FROM core_user
 
 SQLite users
 ------------
@@ -183,11 +183,11 @@ SQLite users
 
   default_pass_scheme = CRYPT
 
-  password_query = SELECT email AS user, password FROM core_user WHERE email='%u' and is_active=1
+  password_query = SELECT email AS user, password FROM core_user u INNER JOIN admin_mailbox mb ON u.id=mb.user_id INNER JOIN admin_domain dom ON mb.domain_id=dom.id WHERE u.email='%Lu' AND u.is_active=1 AND dom.enabled=1
 
   user_query = SELECT '<mailboxes storage directory>/%Ld/%Ln' AS home, <uid> as uid, <gid> as gid, ('*:bytes=' || mb.quota || 'M') AS quota_rule FROM admin_mailbox mb INNER JOIN admin_domain dom ON mb.domain_id=dom.id WHERE mb.address='%Ln' AND dom.name='%Ld'
 
-  iterate_query = SELECT email AS username FROM core_user WHERE email<>''
+  iterate_query = SELECT email AS user FROM core_user
 
 .. note::