During a recent deployment we ran into an issue that had us scratching our heads. The deployment was smooth (once we took care of the 2.4GB mailboxes the executives had), users were happily sending and receiving mail, and all looked great.

This was a simple migration - an Exchange 2003 environment where we added an Exchange 2007 server, and configured it so that mail would route out of the Exchange 2003 environment into the Exchange 2007 server and out to the Internet.

But then we started getting calls from the helpdesk that some users intermittently were able to receive mail, but mail was being held in the outbox. Oddly enough, these calls were from users who had not yet being migrated off of Exchange 2003.

We checked the event log on Exchange 2003. Nothing.

Then we checked the event log on the Exchange 2007 server. There we go.

Event ID 15002 saying that resource pressure is high

"Inbound mail submission from other Hub Transport servers, the Internet, the Pickup directory, the Replay directory, and the Mailbox server, if it is on a Hub Transport server, has stopped."

Oddly enough, there appears to be nothing documented in Exchange 2007 about the ability to change any settings regarding this with PowerShell. Instead, there is a setting you can tweak in a --- believe it or not config file. How 70's!

ACTIONS: Check the \Program Files\Microsoft\Exchange Server\Bin\EdgeTransport.exe.config file. You will see an entry for change the value to something above what your server is listed at in the event log error. I used 80.

Then restart the transport service via the cmdlet with the following command. Restart-service MSExchangeTransport and you will see the mail flow like a river!

Joel Raper
Executive Director of Operations
Azaleos Corporation