XFOR: MSMI Crashes Starting a New Thread, Reads a Null Pointer

The information in this article applies to:

  - Microsoft Exchange Server, versions 4.0 and 5.0

SYMPTOMS

The Microsoft Mail Connector interchange (MSMI) stops processing outbound mail. This can be evidenced by the following symptoms:

• A backlog builds in the message transfer agent's (MTA's) MSMI queue.
• In Performance Monitor, observe thread object "% processor time" counter for all MT.EXE threads. One or more threads above number 3 will show no processor utilization (threads 0 through 3 typically show no processor utilization except during startup, shutdown, or thread and data refresh).
• With MSMI logging set to maximum the application event log will cease logging "Sent" events (ID 2448) (although other MSMI events may still be logged).
• The service stops with no event log warning or DrWtsn32.LOG.
• The service may not respond to control functions nor appear stopped. In the severe, Kill.exe fails to free the service and the computer has to be restarted.

CAUSE

During thread restart, an exception occurs while accessing a [null] pointer in the thread environment block (TEB) that is supposed to hold a pointer to the thread's thread local storage (TLS) area.

STATUS

Microsoft has confirmed this to be a problem in Microsoft Exchange Server version 4.0. A supported fix to this problem is in development, but has not been fully regression-tested and should be applied only to systems experiencing this specific problem. Unless you are severely impacted by this specific problem, Microsoft recommends that you wait for the next Service Pack that contains this fix. Contact Microsoft Technical Support for more information on the availability of this fix.

Microsoft has confirmed this to be a problem in Microsoft Exchange Server version 5.0. This problem was corrected in the latest Microsoft Exchange 5.0 Server U.S. Service Pack. For information on obtaining the service pack, query on the following word in the Microsoft Knowledge Base (without the spaces):

   S E R V P A C K

MORE INFORMATION

The fix moves an initial "new" inside a try/except block. This is already the case for the thread code that processes mail moving out to the proxy postoffice. This prevents this access violation from being fatal.

Keywords          : kbbug4.00 kbbug5.00 kbfix5.00.sp1 XFOR kbusage buglist4.0 buglist5.00
Version           : 4.0 5.0
Platform          : WINDOWS