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Q271568: XCON: MTA Service Does Not Start Due to Event ID 3047

Article: Q271568
Product(s): Microsoft Exchange
Version(s): winnt:5.5
Operating System(s): 
Keyword(s): exc55
Last Modified: 11-JUN-2002

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The information in this article applies to:

- Microsoft Exchange Server, version 5.5 
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IMPORTANT: This article contains information about modifying the registry. Before you modify the registry, make sure to back it up and make sure that you understand how to restore the registry if a problem occurs. For information about how to back up, restore, and edit the registry, click the following article number to view the article in the Microsoft Knowledge Base:

  Q256986 Description of the Microsoft Windows Registry

SYMPTOMS
========

When you attempt to start the Microsoft Exchange Server Message Transfer Agent
(MTA) service, the following Event IDs may appear in the application event log:

  Event ID: 3047
  Source: MSExchangeMTA
  Type: Error
  Category: Configuration
  Description:
  Unable to initialize due to a bad configuration. Too many threads were
  requested. The maximum number is xx, and xxx were requested. Contact
  Microsoft Technical Support. [XAPI MAIN BASE 1] (16)

  Event ID: 9406
  Source: MSExchangeMTA
  Type: Warning
  Category: Resource
  Description:
  There is not enough Performance Monitor memory to display the MTA Connections
  information. Stop attached Performance Monitors and re-start the MTA. [BASE
  MAIN BASE 1] (14)

CAUSE
=====

The MTA does not start due to one or more improperly configured registry keys.
Too many threads are being requested, which does not allow the MTA to start. The
summation of the Decimal value of 4 XAPI thread registry keys plus 3 determines
the total number of threads. This total cannot exceed 75. The following Decimal
value of these registry keys are summed:

  XAPI MA queue threads : REG_DWORD
  XAPI MA threads : REG_DWORD
  XAPI MT queue threads : REG_DWORD
  XAPI MT threads : REG_DWORD

RESOLUTION
==========

WARNING: If you use Registry Editor incorrectly, you may cause serious problems
that may require you to reinstall your operating system. Microsoft cannot
guarantee that you can solve problems that result from using Registry Editor
incorrectly. Use Registry Editor at your own risk.

1. Stop the Message Transfer Agent (MTA) service.

2. Run Regedt32.exe. To do so, click Start, click Run, and then type
  "Regedt32.exe" (without the quotation marks) in the Open: box.

3. Go to the following subkey:

  KEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSExchangeMTA\Parameters

4. Change the Decimal value of the these registry keys (Note: These new values
  are the default values):

  2 for XAPI MA queue threads : REG_DWORD : 0x2
  2 for XAPI MA threads : REG_DWORD : 0x2
  1 for XAPI MT queue threads : REG_DWORD : 0x1
  1 for XAPI MT threads : REG_DWORD : 0x1

5. Close the Registry Editor, and then start the Message Transfer Agent (MTA).

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

The path of the following registry keys is:

  HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSExchangeMTA\Parameters

- XAPI MA queue threads

  REG_DWORD
  0x2
  This value is the number of threads that handle interaction with the MTA on
  behalf of the following clients:
  - MDB and XAPI MA Delivery Queue clients.
  - XAPI MA Retrieval Queue clients.

- XAPI MA threads

  REG_DWORD
  0x2
  This value is the number of threads that handle calls from the following
  clients:
  - MDB and XAPI MA Delivery Queue clients.
  - XAPI MA Retrieval Queue clients.

- XAPI MT queue threads

  REG_DWORD
  0x1
  This value is the number of threads that handle interaction with the MTA on
  behalf of XAPI MT Gateway clients.

- XAPI MT threads

  REG_DWORD
  0x1
  This value is the number of threads that handle calls from XAPI MT Gateway
  clients.

- XAPI/MMI client DMOD threads

  REG_DWORD
  0xa
  This value is the maximum number of MTA DMOD threads to handle connections to
  the following clients:
  - MDB and XAPI MA Delivery Queue clients.
  - XAPI MA Retrieval Queue clients.
  - XAPI MT Gateway clients.
  - MMI clients.

All MTA DMOD threads (of whatever type) can support multiple connections.
Connections are load-shared over threads of the same type.


Additional query words:

======================================================================
Keywords          : exc55 
Technology        : kbExchangeSearch kbExchange550 kbZNotKeyword2
Version           : winnt:5.5
Issue type        : kbprb

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