DOCUMENT:Q187929  05-MAY-1999  [exchange]
TITLE   :XCON: Recovery Checkpoint Size Different, MTA Connection Fails
PRODUCT :Microsoft Exchange
PROD/VER:WINDOWS:5.0,5.5
OPER/SYS:
KEYWORDS:

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The information in this article applies to:

 - Microsoft Exchange Server, versions 5.0, 5.5 
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SYMPTOMS
========

When the message transfer agent (MTA) on one Microsoft Exchange Server computer
attempts to connect to the MTA on another Exchange Server computer, it proposes
a particular checkpoint size. When the second MTA accepts the connection, it may
propose a different checkpoint size. If the connection ends unexpectedly, the
first MTA attempts to connect again. However, the second MTA may not propose the
same checkpoint size that it originally proposed, even if the first MTA does.

Note that if the first MTA established a monologue connection, the inconsistency
between the original session protocol data unit (SPDU) and the recovery SPDU may
prevent the first MTA from reconnecting after the original connection ends.

STATUS
======

Microsoft has confirmed this to be a problem in Microsoft Exchange Server
version 5.0.


A supported fix is now available, 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.


Microsoft has confirmed this to be a problem in Microsoft Exchange Server version
5.5. This problem has been corrected in the latest U.S. service pack for
Microsoft Exchange Server version 5.5. 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


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Keywords          :  
Technology        : kbExchangeSearch kbExchange500 kbExchange550 kbZNotKeyword2
Version           : WINDOWS:5.0,5.5
Issue type        : kbbug
Solution Type     : kbfix

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