We are using Sophos Gateway and routing email out of Microsoft 365 through a Sophos Smarthost. When a user sends an email that fails to be delivered due to the recipient address being misspelled or the recipient not existing the senders never receive an NDR. Sophos shows the message as failed along with the reason that was reported from the recipient server. Is there a setting to allow Sophos to pass the NDR from the recipient server back to the sender or am I missing something else?
Sophos Email customers using IP-based mailflow rule connectors must migrate to certificate-based configuration by March 31st. To see if you're affected Click Here.
