When you rename the domain in the Parallels Plesk Panel to the same name as the hostname, the mail stops to deliver to its mailboxes. The following error occurs:
postfix/trivial-rewrite: warning: do not list domain plesk95.postfix in BOTH virtual_alias_domains and virtual_mailbox_domains postfix/smtpd: disconnect from unknown[127.0.0.1] postfix/error: 7320411367F3: to=<firstname.lastname@example.org>, relay=none, delay=8, delays=8/0.01/0/0.01, dsn=5.0.0, status=bounced (User unknown in virtual alias table)
The following steps will reproduce the above error:
Install the Parallels Plesk Panel with the hostname centos.plesk, for example. Create the domain. Rename the domain to centos.plesk. Add a mailbox to this domain and try to send\receive mail. The result will be the error above.
If you need a domain with the same name as your current hostname, we recommend changing your current hostname:
# /usr/local/psa/bin/server_pref -u -hostname <new_hostname>
NOTE: Changing your hostname can require additional reconfiguration of the SSO if you have Customer & Business Manager installed.