A mail server is set to relay the outbound mails to TMEMS, but fails and rejects the mails. It then displays the following error:
554 5.7.1 <recipient address>: Recipient address rejected: NO-DOMAIN.
This issue occurs if the outbound IP address for the domain is not added.
Follow these steps to resolve the issue:
- Log on to the TMEMS web console, and go to Domains page.
- Click the related domain which will send the outbound mails to TMEMS.
- Make sure that "Enable outbound protection" is enabled, and the related outbound IP is listed in the allow relay list.