Problem: Email Clients Get Logged Out or Suddenly Do not Have Access to Their Mailbox

mail
dovecot
problem

#1

Problem

Email clients (like Thunderbird or Outlook) get logged out or suddenly do not have access to their mailbox.

Environment

Users have a bunch of different ways to authenticate to Dovecot. They might use any combination of “username” and “domain”:
Logging in with username@domain or just “username”.

Dovecot does not have the concepts of domains so above users are two different users for Dovecot.

Solution

Option 1

Make sure your users all use “username@domain” as credentials for the IMAP service.

Option 2

Note There is no configuration option from UCS so the following settings might get lost during an update.

To make sure users will get the correct mailbox even when logging in without domain name use the following setting to activate a default domain.

echo "auth_default_realm = domain.de" >/etc/dovecot/conf.d/10-disable-plain-login.conf
systemctl restart dovecot 

Option 3

Note There is no configuration option from UCS so the following settings might get lost during an update.

To disallow domain-less logins use the following settings:

echo "auth_default_realm = no.such.domain.de" >/etc/dovecot/conf.d/10-disable-plain-login.conf
systemctl restart dovecot 

#2

#3

#4

Dovecot seltsame Userordern im Hauptverzeichnis