We have recently deployed Exchange 2010 along with Outlook 2007 clients. We have an e-mail which is generated by a perl script on a linux system which on our old e-mail system was working fine but on Exchange 2010/Outlook 2007 part of the body of the message is being split and put into several attachments named att00001.txt att00002.txt etc. If I send the same e-mail to a Lotus Domino/Notes client the message reads as expected and there are no attachments. Similarly if I send the same message to gmail it has no issues. Pasted below is the plain text [view original] contents from gmail in case it helps somebody work out why Exchange/Outlook are mangling the message like this: This is a multi-part message in MIME format. --_----------=_127166772049950 Content-Disposition: inline Content-Length: 459 Content-Transfer-Encoding: binary Content-Type: text/plain Out-of-hours System Cover Rota If you receive a call who needs support after business hours, please refer If you need to contact the support advisor on duty directly about a systems issue, please use . Systems cover rota for the week commencing Mon April 26, 2010 --_----------=_127166772049950 Content-Disposition: inline Content-Length: 67 Content-Transfer-Encoding: binary Content-Type: text/plain; charset="UTF8" MIME-Version: 1.0 X-Mailer: MIME::Lite 3.01 (F2.73; B3.01; Q3.01) Date: Mon, 19 Apr 2010 09:02:00 UT Tue April 20, 2010 Night (17:30 - 09:00) patrick --_----------=_127166772049950 Content-Disposition: inline Content-Length: 67 Content-Transfer-Encoding: binary Content-Type: text/plain; charset="UTF8" MIME-Version: 1.0 X-Mailer: MIME::Lite 3.01 (F2.73; B3.01; Q3.01) Date: Mon, 19 Apr 2010 09:02:03 UT Wed April 21, 2010 Night (17:30 - 09:00) patrick --_----------=_127166772049950 Content-Disposition: inline Content-Length: 67 Content-Transfer-Encoding: binary Content-Type: text/plain; charset="UTF8" MIME-Version: 1.0 X-Mailer: MIME::Lite 3.01 (F2.73; B3.01; Q3.01) Date: Mon, 19 Apr 2010 09:02:07 UT Thu April 22, 2010 Night (17:30 - 09:00) patrick

The same symptom will occur when an attachment body part in an e-mail message is sent before the message body part of the e-mail message is sent, as described in the KB 969854 Also, the issue could also happen if the message has multi-part body content. Please post the message header of the problematic message, and check if the content-type is multipart/mixed. Given a message with a multipart/mixed root, exchange will only display the first part as the body and others as the attachment, which is by design. The workaround is, to re-compose the problematic message on the transport server by using customized event sink. You can use “Development” forum for the advice about the writing of the event sinkJames Luo TechNet Subscriber Support (http://technet.microsoft.com/en-us/subscriptions/ms788697.aspx) If you have any feedback on our support, please contact tngfb@microsoft.com