I have an issue and I cannot find a resolution to the problem. We use an exchange 2010 server, configured to use a smarthost, which is a smartemail server. If a mail is sent out and a NDR is generated the mail is returned to exchange and it immediately becomes a .bad mail in the replay folder, the headers before the mail is changed is

Message-ID: <634897879470655925@smtp40.hostworx.co.za>
From: "System Administrator"
To: eugene@lightfibre.co.za
Date: Thu, 29 Nov 2012 12:12:27 +0200
Subject: Delivery Failure

and after the mail is renamed to bad, it is supposed to use x-headers, but this is what the mail looks like, however notice the X-sender is missing.

x-receiver: eugene@lightfibre.co.za
Message-ID: <634897879470655925@smtp40.hostworx.co.za>
From: "System Administrator"
To: eugene@lightfibre.co.za
Date: Thu, 29 Nov 2012 12:12:27 +0200
Subject: Delivery Failure

if the header x-sender:  postmaster@lightfibre.co.za is inserted into the mail and renamed to .eml the mail gets deleivered fine to the mailbox, so it seems that microsoft takes the mail sees "system administrator" ie a null sender and fails and then re-creates the mail witout the x-sender header.

I have checked on the transport properties, to accept non deleivery and delivery reports is checked, so I am not sure how to resolve this issue.

What is the flow path for your return emails?  Do they go to the smarthost and then Exchange or directly to Exchange?

Hi,

sorry its that time of the year,  the mails come into the smartermail server and then they messages are popped off to the exchange server, via a 3rd party pop collector, this then puts these messages into the folder where exchange then checks it and deleivers it.

the weird part is the messages are delivered to exchange 100% identical to the messages received by smartermail.

We have exactly the same Issue with a diffrent Mail Relay System. Did you ever find a solution?

nope no answer to this issue as of yet