Views:
The issue occurs because the recipient's domain name (example.com) is not in the Relay Domains list. To resolve this:
  1. Go to the IMSS management console and click Administration > IMSS Configuration > SMTP Routing > Message Rule.
  2. Add the domain name (example.com) in the Relay Domains list and click Save.
If the issue still persists, please contact Trend Micro support.
Keywords: 550 domain of forward path is not allowed,error message appears and mails are not delivered,delivery failure of mails,550 domain of forward path mail delivery error