Got a new one based on this info. We started SRS and it seemed to help, but now I have a specific email hoster that is rejecting email with 550 Unable to Relay when SRS is turned on. I turn it off and they can get the email.
An email is sent to firstname.lastname@example.org. The email is set to forward to 4 emails address on 2 different domains outside of SmarterMail. For 1 domain it makes it. For the other we get the 550 Unable to Relay bounce.
That makes no sense now! UGH