KnowledgeBase Archive

An Archive of Early Microsoft KnowledgeBase Articles

View on GitHub

Q257727: XCON: Slow Mail Flow Across X.400 with 289 and 1294 Warnings

Article: Q257727
Product(s): Microsoft Exchange
Version(s): winnt:4.0,5.0,5.5
Operating System(s): 
Keyword(s): exc4 exc5 exc55
Last Modified: 30-APR-2000

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

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

SYMPTOMS
========

The two following error messages may be displayed:

  Event ID - 289
  Source - MSExchangeMTA
  Description - A connection to 1% could not be opened.

  Event ID -1294
  Source - MSExchangeMTA
  Description - An association with entity 1% ended abnormally.

Messages also intermittently back up on a message transfer agent (MTA) queue for
an X.400 Connector to a remote site. When you stop and restart the MTA, mail
flow resumes.

CAUSE
=====

This issue can occur as a result of poor network quality.

WORKAROUND
==========

To work around this issue:

1. Open the X.400 Connector properties, and click the Override tab.

2. Under the Request to Send (RTS) values, set Checkpoint Size to 10 (30 is the
  default), and Window Size to 3 (default value is 5). In the Association
  Parameters box, set Disconnect to 360 (default value is 120).

3. Stop and restart the MTA service.

Mail flow should resume and continue.

MORE INFORMATION
================

Checkpoint size. Sets the amount of data to be transferred before a checkpoint
is inserted. If an error occurs and the message must be retransferred, the
process restarts from the most recent checkpoint. If you specify zero, no
checkpoint is set. If you use a checkpoint, you slightly reduce the transmission
speed. Decrease the checkpoint size when the connection is less reliable.

Window size. The number of checkpoints that can go unacknowledged before data
transfer is suspended. The greater the window size, the greater the transfer
rate. The window size determines the amount of resources set aside for the
receiving station. Specify window size only if the checkpoint size is greater
than zero.

Disconnect. The amount of time to wait before a connection is terminated because
of a previously terminated association.

Additional query words: XMRP

======================================================================
Keywords          : exc4 exc5 exc55 
Technology        : kbExchangeSearch kbExchange500 kbExchange550 kbExchange400 kbZNotKeyword2
Version           : winnt:4.0,5.0,5.5
Issue type        : kbprb

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

THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY.