Mail account login does not work after upgrade to Plesk Onyx. Webmail shows an error:
server responded: -ERR login failed
Mail server is configured for using Courier-IMAP mail delivery agent, that is not running:
# service courier-imap status
Loaded: not-found (Reason: No such file or directory)
Active: inactive (dead)
Courier-IMAP component is not shown in Plesk > Tools & Settings > Services Management
The service cannot start from command line with "
unknown service" error.
Service configuration corruption
1. Launch Plesk autoinstaller:
# plesk installer
2. Install Dovecot IMAP/POP3 server
3. Launch Plesk autoinstaller and install Courier-IMAP back