- Plesk for Linux
A mailbox with "+" sign in user name was created;
Webmail login fails, the following error can be found in
CONFIG_TEXT: NO [AUTHENTICATIONFAILED] Authentication failed
Following lines can be found in
CONFIG_TEXT: dovecot: imap-login: Disconnected (auth failed, 2 attempts in 13 secs): user= firstname.lastname@example.org , method=PLAIN, rip=::1, lip=::1, TLS: Disconnected, session=<1OM4LIxfnOgAAAAAAAAAAAAAAAAAAAAB>
The issue is caused by
feature which is used to deliver mail to a specific folder. For example, mail for email@example.com will be delivered to a folder named
in the user's mailbox.
To disable subaddressing and allow to use "+" in the email username, perform following steps:
Connect to the server via SSH ;
Comment out the
# sed -i 's/recipient_delimiter/#recipient_delimiter/' /etc/postfix/main.cf
Add "+" sign to the
# grep auth_username_chars /etc/dovecot/dovecot.conf
auth_username_chars = abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@+'
Restart mail services:
# service dovecot restart
# service postfix restart
Navigate to Domains > example.com > Email Addresses and recreate the mailbox.