Incoming Emails Blocked for Unknown Reason on Both RoundCube and Outlook

  • updated
  • Answered

Incoming roundcube and outlook emails are being returned with error message

Reported error:

550 5.0.350 Remote server returned an error -> 550 Email blocked by

DSN generated by:


IMH Support Agent 1
  • Answered


Thank you for contacting us regarding incoming emails being blocked. This error message seems to indicate the emails are being flagged and blocked by the spam filter, due to being included on a blacklist managed by "".

In this case, the sender should request a delisting or reach out to whoever manages their mail server to do so.

Thank you,