Microsoft KB Archive/176488

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Last reviewed: February 2, 1998

Article ID: Q176488 The information in this article applies to:

- Microsoft Server, Version(s) 5.0

SYMPTOM
After restarting a Microsoft Exchange Server that has been off-line for a few hours or days, the Message Transfer Agent (MTA) may start rejecting messages, holding messages in the queues and/or create message loops. All of these symptoms will contribute to degraded system performance and slow mail flow. Some error messages to check for would be as follows: Event ID 200 Source MSExchangeMTA Type Warning Category X.400 Service Description An error occurred while ASN.1 was decoding an object (dump reference 192). [limit exceeded on set of or sequence of 30464 2614 1spdi 192 MTA XFER-IN 15 97] Event ID 2024 Source MSExchangeIS Private TypeError Category MTA Connections Description: Unable to access the object manager (OM) object from the Microsoft Exchange MTA for MH_T_ALTERNATE_RECIP_ALLOWED, MH_T_CONVERSION_LOSS_PROHIBITED, etc.

CAUSE
The behavior has been seen when the MTA Open Interval time is set very low. These settings are located in a few places depending on the setup. The global setting is located under Site >> Configuration >> MTA Site Configuration >> Messaging Defaults. The Administrator may also set these on individual X400 and Dynamic RAS connectors. It will be located on each of these connectors Messaging Defaults tabs on their respective property pages. MORE INFORMATION The Open Interval time is used to determine how long the MTA should wait before attempting an association to another MTA. The default is 600 seconds, which should suffice in most situations. The lowest value that can be entered is 15 seconds, however setting it this low will create the above problem if the MTA has to handle a large volume of messages, such as restarting after a maintenance period. It is recommend that this setting is never below 30 seconds on a LAN and 60 seconds on a RAS connection.
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