Update: We are also getting complaints for normal accounts, not just aliases. Comparing SMTP sessions before the 7320 update and now show no differences.

We're getting reports of the same issue.

Maybe a side effect from the fix for the NDR that were not returned when using an outgoing gateway?

7320:

FIXED: The NOTIFY attribute for forwarded message recipients is always set to NEVER. 

FIXED: Failed delivery DSN messages should be properly handled when the message has no NOTIFY flag.

Chris & Shaun -

Are you guys currently using outbound gateways? It might help us determine if this is related to either of the items that Sébastien mentioned.

We are not

We are. 

We're getting lots of reports of this issue now.

Hello,

Chris/Shaun could you DM me a session from your logs that exhibits this behavior. I want to try and match this behavior with our test boxes here and see if I notice anything. I'm going to give this particular issue some focus as those bounces could cause some issues.

DM'd you Matt.

Here's the message from one of our users:

"my email seems to be sending out messages to people who try to email me.  I'm still getting the messages, but they are getting this error message.  Doesn't seem to be everyone, just a few let me know."

I'm wondering if it's related to forwarding from a User with forwarding enabled, or maybe also from an alias.  I'm going to create an account for testing shortly.  Interesting that our customer says she's still receiving the emails but the person who sent it in the first place is getting notification that it wasn't sent.  I can see that as confusing and concerning.

Hi Matt,

Did you have any luck with the logs that Chris sent you?  I so far haven't been able to reliably replicate the issue but we're getting lots of complaints about it.

Shaun

We have about 20 tickets open right now, I expect we will receive more. Users have also stated aside from receive empty

Remote Server returned: '' 

But we also have complaints of

Remote Server returned '< #5.0.0>'

Chris could you send me a full log copy for the session which demonstrated.

Remote Server returned '< #5.0.0>'

The log you sent me looked to follow this flow. I just got done doing some testing with no luck.
SMTP Client Authed -> Spool, recipient was a different (but local) domain -> the intended recipient and the sender receive messages.

However, this message above, "Remote Server returned", implies that it is a recipient on a remote server, I have not exhausted this avenue. A log would help me there. I'll be attempting this right now a bit harder though since it is potentially remote.

DM'd you a few messages Matt, sorry. From what I notice... The delivery failure email is going out before SM even attempts to delivery to the remote address.

[2020.01.21] 15:33:52.470 [39948] Sending remote mail for 0100016fca3ce80d-a52af255-67fa-4410-a151-26bc3ebaaccb-000000@amazonses.com

SM doesnt attempt delivery to the user until 15:33:52, however, SM delivery logs show that the bounce was being sent before it at 15:33:27

[2020.01.21] 15:33:27.929 [39953] Skipping spam checks: Bounce
[2020.01.21] 15:33:28.023 [39953] MxRecord count: '1' for domain 'amazonses.com'