Cannot send or receive emails with attachments with Exchange 2010

The Bottom Line: make sure your Exchange security solution/anti-virus is operating properly. Details below.

Here's an oddball issue we had this morning.

We are in the process of an Exchange migration from Exchange 2003 to a clustered Exchange 2010 environment. We had failed over our cluster to do some maintenance on one node and over the weekend we did some patches, and updated our hardware load balancers. When we came in Monday morning some issues were having problems sending and/or receiving emails with attachments. We also have a front-end servers load balanced via a Citrix Netscaler and we did maintenance on that HA pair this weekend as well (we know, too many changes :) ).

An odd symptom was that we couldn't see any mails with attachments in the Outlook client, but if we logged into the Outlook Web App we could see the mail in our mailbox but received a rather nasty .Net Exception error when we tried to view or open the mail.

The Exception was:

Exception type: Microsoft.Mapi.MapiExceptionCallFailed
Exception message: MapiExceptionCallFailed: Unable to get properties on object.

A Google searched revealed a thread on the Social TechNet threads about someone receiving a similar error when trying to view mail via the Outllook Web App. In the thread a Microsoft engineer asked the user if they were running Forefront (Microsoft's Security Suite which includes anti-virus solutions for Exchange Server). That gave our Exchange administrator an idea to check on our security solution. Sure enough, the AV service installed on the Exchange server wasn't started.

It appears as if Symantec Messaging Security for Microsoft Exchange either sets up an Active Directory account, or prompts the installing user to create one. The service then uses those credentials to run the AV server. In our Active Directory domain, account passwords are required to be changed after a set period. It appears that the user as which the SMSME service was running had an expired password and the service wouldn't start. As a result, standard email would be delivered however anything that had an attachment to be scanned would be processed by Exchange but then subsequently fail an AV scan and the message went into the bit bucket.

Checking the box in Active Directory Users and Computers for the user's password to never expire allowed the service to start properly and emails with attachments started flowing again.

So check your AV software ;)