Attempts to send a message from the Plesk server to a mailbox on
example.comfails with one of the errors below:
# tail -f /usr/local/psa/var/log/maillog | grep 'unknown in virtual mailbox'
550 5.1.1 [email protected]: Recipient address rejected: User unknown in virtual mailbox table; [email protected] [email protected]
example.com postfix-local: cannot chdir to mailname dir contact: No such file or directory
example.com postfix-local: Unknown user: [email protected]
ME-E0103:  Local Delivery: Failure - Domain for ([SMTP:[email protected]]) is locally serviced, but recipient is not defined in address map.
In webmail, the following error might occur:
Could not send message to SMTP server. Check you have access to send messages via the server and that all To/CC/BCC addresses are valid
Error: SMTP Server rejected email. Returned:550 sorry, no mailbox here by that name. (#5.7.17)
Error SMTP (500): The following recipient could not be reached "[email protected]" (sorry, no mailbox here by that name. (#5.7.17)).
There was an error sending your message: Message could not be delivered - the address was not found, is unknown, or is not receiving messages.
550 5.1.1 [email protected] ... User unknown (in reply to MAIL FROM command))
example.com is hosted on the Plesk server but the mail for the domain is hosted on an external mail server/service.
Mail server treats
example.com as a local domain and tries to send emails locally.
Note: In some cases, the mail service is necessary locally and externally.
Vote the UserVoice request as top-voted suggestions are likely to be implemented in future Plesk updates.