XADM: OpenMsgStore Function Is Not Thread Safe

If a program is running multiple threads that both run OpenMsgStore repeatedly, a deadlock may occur after some time.

This issue can occur if a thread (T1) is holding a critical section object (CS1) and is waiting for another critical section (CS2) that is being held by another thread (T2) that is waiting for the critical section (CS1), which leads to a deadlock situation.

To resolve this problem, obtain the latest service pack for Exchange Server 5.5. For additional information, click the following article number to view the article in the Microsoft Knowledge Base:

Microsoft has confirmed that this is a problem in Microsoft Exchange Server version 5.5. This problem was first corrected in Exchange Server 5.5 Service Pack 4.