DOCUMENT:Q192440  20-MAY-2002  [exchange]
TITLE   :XADM: Backup Stops Because of Communications Error
PRODUCT :Microsoft Exchange
PROD/VER:WinNT:4.0,5.0,5.5
OPER/SYS:
KEYWORDS:exc55sp2fix

======================================================================
-------------------------------------------------------------------------------
The information in this article applies to:

 - Microsoft Exchange Server, versions 4.0, 5.0, 5.5 
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SYMPTOMS
========

Backup stops because of a communications error.

CAUSE
=====

When backing up to NULL or buffering the read bytes from HRBackupRead, the
client and server may stop responding (hang) while waiting on each other. A
communications error will be produced, causing the backup to be halted.

This problem is seen more often in single processor environments than in
multi-processor environments.

RESOLUTION
==========

Exchange Server 4.0
-------------------

A supported fix that corrects this problem is now available from Microsoft, but
has not been fully regression-tested and should be applied only to computers
experiencing this specific problem. To resolve this problem immediately, contact
Microsoft Product Support Services to obtain the fix. If you are not severely
affected by this specific problem, Microsoft recommends that you wait for the
next Microsoft Exchange Server version 4.0 service pack that contains this fix.

For a complete list of Microsoft Product Support Services phone numbers and
information on support costs, please go to the following address on the World
Wide Web:

   http://support.microsoft.com/default.aspx?scid=fh;EN-US;CNTACTMS




Exchange Server 5.0
-------------------

A supported fix that corrects this problem is now available from Microsoft, but
has not been fully regression-tested and should be applied only to computers
experiencing this specific problem. To resolve this problem immediately, contact
Microsoft Product Support Services to obtain the fix. If you are not severely
impacted by this specific problem, Microsoft recommends that you wait for the
next Microsoft Exchange Server version 5.0 service pack that contains this fix.

For a complete list of Microsoft Product Support Services phone numbers and
information on support costs, please go to the following address on the World
Wide Web:

   http://support.microsoft.com/default.aspx?scid=fh;EN-US;CNTACTMS




Exchange Server 5.5
-------------------

To resolve this problem, obtain the latest service pack for Exchange Server
version 5.5. For more information, please see the following article in the
Microsoft Knowledge Base:

   Q191014 XGEN: How to Obtain the Latest Exchange Server 5.5 Service Pack




STATUS
======

Microsoft has confirmed this to be a problem in Microsoft Exchange Server
versions 4.0, 5.0, and 5.5.
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Keywords          : exc55sp2fix 
Technology        : kbExchangeSearch kbExchange500 kbExchange550 kbExchange400 kbZNotKeyword2
Version           : WinNT:4.0,5.0,5.5
Issue type        : kbbug
Solution Type     : kbfix

=============================================================================

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