Knowledge Base

XFOR: IMC Appears Hung with Improper DN Format

Article ID: 166540

Article Last Modified on 10/28/2006

Microsoft Exchange Server 4.0 Standard Edition
Microsoft Exchange Server 5.0 Standard Edition

This article was previously published under Q166540

SYMPTOMS

The Internet Mail Connector (IMC) or Internet Mail Service may stop processing mail and a mail backlog may build in the connector's mailbox in the Information Store (MTS-OUT).

Under the debugger, the connector's threads appear inactive and waiting on a critical section.

CAUSE

An improperly formatted distinguished name (DN) causes the IMC or IMS to overwrite memory and corrupt the heap.

STATUS

Microsoft has confirmed this to be a problem in Microsoft Exchange Server version 4.0. This problem has been corrected in the latest U.S. Service Pack for Microsoft Exchange Server version 4.0. 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

Microsoft has confirmed this to be a problem in Microsoft Exchange Server version 5.0. This problem has been corrected in the latest U.S. Service Pack for Microsoft Exchange Server version 5.0. 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

This is a very isolated case in which a third-party product, Baranof's MailCheck, was set up with a DN that looked like the following:

   /O=ORGNAME=OU=SITENAME

A proper DN should look like /O=ORGNAME/OU=SITENAME. Baranof's software does not check the validity of the DN when entered during the product's setup. As a result, messages sent from MailCheck contain this incorrect DN and caused the IMC to seem to stop responding.

With the fix applied, the IMC or IMS validates the DN before writing it into memory.

MailCheck is manufactured by Baranof's, a vendor independent of Microsoft; we make no warranty, implied or otherwise, regarding this product's performance or reliability.

Additional query words: crash hang

Keywords: kbhotfixserver kbqfe kbbug kbfix kbusage KB166540