- Mailman is installed on the server and configured in Domains > example.com > Email Addresses > Mailing Lists
- Unable to send emails to mailing list, following error can be found in
hostname.example.com postfix/smtpd: NOQUEUE: reject: RCPT from mail.example.com[203.0.113.2]: 550 5.1.1 <[email protected]>: Recipient address rejected: User unknown in virtual mailbox table; from=<[email protected]> to=<[email protected] proto=ESMTP helo=<some_mail_server>
/var/spool/postfix/plesk/virtualdoes not contain mail-list address:
# postmap -s /var/spool/postfix/plesk/virtual | grep [email protected]
- Server hostname was changed recently that can be confirmed in
/var/log/maillogwhere different hostname was displayed some time ago:
Mar 18 05:35:29 hostname1.example.com postfix/smtpd
Sep 08 15:22:00 hostname.example.com postfix/smtpd
Plesk bug PPPM-7494 that has been fixed in Plesk 17.8 MU 11.
Upgrade to the latest Plesk version.
As a workaround
- Login into Plesk
- Switch off/on mailing in Domains > example.com > Email Addresses > Mailing Lists > [email protected]