XCCC: Instant Messaging Server Stops Processing Clients with High Outgoing Messages (318158)

The information in this article applies to:

Microsoft Exchange 2000 Server

This article was previously published under Q318158

SYMPTOMS

Instant Messaging Server may stop responding to client requests intermittently. During that time, Instant Messaging clients cannot log on and existing clients that try to update their status are logged off.

CAUSE

When the internal working queue length exceeds 1024, all the incoming messages are returned as service unavailable (503 error).

RESOLUTION

To resolve this problem, obtain the latest service pack for Microsoft Exchange 2000 Server. For additional information, click the following article number to view the article in the Microsoft Knowledge Base:

301378 XGEN: How to Obtain the Latest Exchange 2000 Server Service Pack

The English version of this fix should have the following file attributes or later:

Component: Instant Messaging

File name	Version
Msimsrv.dll	6.0.5770.57
Msimcfg.dll	6.0.5770.57
Msimnetc.dll	6.0.5770.57

NOTE: Because of file dependencies, this update requires Microsoft Exchange 2000 Server Service Pack 2.

STATUS

Microsoft has confirmed that this is a problem in Microsoft Exchange 2000 Server. This problem was first corrected in Microsoft Exchange 2000 Server Service Pack 3.

MORE INFORMATION

This fix does the following:

Modifies the work queue to count only incoming messages. If the incoming queue is too large, the Service Unavailable Error (503 Error) is returned. If not, outgoing messages are queued without affecting incoming messages.
Allows the work queue to be configurable by the following registry key:
HKEY_LOCAL_MACHINE\Software\Microsoft\Exchange\InstantMessaging\MaxOutstandingInboundMsgs
If this key does not exist, the default value is 1024.
Changes the number of retries from seven retries to four retries. This allows the outgoing message queue to expire faster if there are network issues that are keeping outgoing messages from being sent.

Modification Type:	Minor	Last Reviewed:	6/5/2003
Keywords:	kbbug kbExchange2000preSP3fix kbExchange2000sp3fix kbfix KB318158