Hi, I'd like to find a way to stop Exchange from mangling NDRs received from a 3rd-party. I've recently setup SBS 2011 and have my e-mails split externally to two POP boxes (until I'm happy that the setup isn't bouncing/eating mails it shouldn't). I'm checking one with my old mail client, and the other with Exchange via SBS POP3 connector. This lets me see the difference between receiving the NDR directly, and via Exchange. My problem is that Exchange has successfully truncated the REASON the e-mail bounced, whereas the non-Exchange copy is perfectly clear what happened. Is there a way to stop Exchange intercepting NDRs and doing its own thing? The two versions are below. E-mail addresses, IPs and server names have been changed for anonymity. Non-Exchange version Subject: Returned mail: see transcript for details Auto-Submitted: auto-generated (failure) The original message was received at Thu, 30 Jun 2011 18:14:11 +1000 from my.ip.address [123.123.123.456] ----- The following addresses had permanent fatal errors ----- <recipient@domain.name> (reason: Insufficient permission) (expanded from: <recipient@domain.name>) ----- Transcript of session follows ----- Mail quota exceeded. 550 5.0.0 <recipient@domain.name>... Insufficient permission Reporting-MTA: dns; mail12.domain.name Received-From-MTA: DNS; my.dns.domain Arrival-Date: Thu, 30 Jun 2011 18:14:11 +1000 Original-Recipient: rfc822;recipient@domain.name Final-Recipient: RFC822; recipient@domain.name X-Actual-Recipient: RFC822; /m33/O/fr/recipient@mailserver.domain.name Action: failed Status: 5.3.0 Diagnostic-Code: X-Unix; 77 Last-Attempt-Date: Thu, 30 Jun 2011 18:14:12 +1000 Return-Path: <my@email.address> Exchange version Delivery has failed to these recipients or groups: recipient@domain.name Your message couldn't be delivered. Try to send it again later. If the problem continues, please contact your helpdesk. Diagnostic information for administrators: Generating server: mailserver.domain.name recipient@domain.name #< #5.3.0 X-Unix; 77> #SMTP# Original message headers: Return-Path: <my@email.address>

Stop using the POP3 connector would be the obvious answer. The POP3 connector isn't perfect - it has to reformat the messages and therefore information may be lost. However on what you have posted, it would appear that the NDR that is being generated isn't correctly formatted and therefore Exchange is making the best it can from the information. Exchange tries to make the NDR more user friendly and that behaviour cannot be changed. Simon.Simon Butler, Exchange MVP Blog | Exchange Resources | In the UK? Hire Me.

I had planned on removing the POP3 connector, once I was sure Exchange wasn't going to eat (no delivery and no NDR) my mail, which it did this morning. I've just reconfigured my Postfix mail server to do the mail splitting, so I can remove the POP3 connector and still get non-Exchange copies of my mail. We'll see if it makes any difference. How does Exchange detect when an e-mail is an NDR? Is it just the sender being MAILER-DAEMON? I could just do an address rewrite through Postfix to stop it making the NDRs "more user friendly".

Hi, By default, the ExternalPostmasterAddress parameter on the Set-TransportServer cmdlet is not set. When the ExternalPostmasterAddress parameter is not set, the external postmaster SMTP address defaults to Postmaster@<Authoritative Domain>. The authoritative domain that is used to create the postmaster address is the default accepted domain. You can view the default accepted domain by using the Get-AcceptedDomain cmdlet. For more information, please refer to the following article: http://technet.microsoft.com/en-us/library/bb400930(EXCHG.80).aspx Thanks. Novak Wu TechNet Subscriber Support in forum If you have any feedback on our support, please contact tngfb@microsoft.com Please remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

How is thing going on? If there is any progress or question, please feel free to post it here. Regards, Novak Wu TechNet Subscriber Support in forum If you have any feedback on our support, please contact tngfb@microsoft.com Please remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.