XCON: Performance Monitor Work Queue and MTA Queues Tab Conflict

When you view the Performance Monitor Work queue, there may be a certain number of items always present. At the same time, the MTA Queues tab in the Exchange Server Administrator program may show a conflicting number of items.

Messages with deferred delivery may appear in the Performance Monitor Work Queue and may not be accounted for on the MTA Queues tab. Also there may be a "broken pointer" to the Db00002b.dat file. The Performance Monitor Work Queue counter points to this file for an accurate reading of the amount of messages to be processed. Occasionally, this pointer or the file produces an inaccurate reading.

To resolve this problem, perform the following steps:

1. Stop the Message Transfer Agent (MTA) service in the Control Panel Service icon.
2. For Exchange Server versions 4.0 and 5.0, go to the <drive>:\Exchsrvr\MTADATA directory, and rename the Db00002b.dat file.
   
   For Exchange Server version 5.5, rename the Db000027.dat file.
3. For Exchange Server 4.0, 5.0, and 5.5, run mtacheck /v at least two times. This is the preferred method to recreate the queue within the MTADATA directory.
   
   For Exchange Server 5.5 Service Pack 1 and later, do not run mtacheck /v if the work queue file has been renamed. Doing so causes an access violation that results in the work queue not being rebuilt. Instead, use Mtacheck.exe version 5.5.1960 from the Exchange Server 5.5 CD, which should rebuild the work queue file.
4. Restart the MTA service. The Performance Monitor should report the correct number of items in the MTA work queue.

There is no guarantee that the work queue .dat file in Exchange Server 5.5 will always be Db000027.dat. In cases where the server was upgraded from an earlier version, the work queue can be named Db00002b.dat.

To verify which file is the work queue, run mtacheck /v /f mtacheck.log, and locate the work queue designation from the Mtacheck.log file.