DOCUMENT:Q169319  09-MAY-1999  [exchange]
TITLE   :XFOR: Performance Tuning the PCMTA
PRODUCT :Microsoft Exchange
PROD/VER:WinNT:4.0,5.0
OPER/SYS:
KEYWORDS:

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The information in this article applies to:

 - Microsoft Exchange Server, versions 4.0, 5.0 
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IMPORTANT: This article contains information about editing the registry.
Before you edit the registry, make sure you understand how to restore it if
a problem occurs. For information about how to do this, view the "Restoring
the Registry" Help topic in Regedit.exe or the "Restoring a Registry Key"
Help topic in Regedt32.exe.

SUMMARY
=======

Administrators of Microsoft Exchange Server versions 4.0 and 5.0 have the
ability to tune the Microsoft Mail Connector (AppleTalk) MTA (PCMTA); the
component that facilitates communication between Exchange and Microsoft Mail for
PC Networks.

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

Tuning takes the form of three registry settings associated with the PCMTA
service created by the installer of the Microsoft Mail Connector. That name will
be declared on the connector's MTA tab. In this article, the service will be
called Legacy Mail Connector.

WARNING: Using Registry Editor incorrectly can cause serious problems that may
require you to reinstall your operating system. Microsoft cannot guarantee that
problems resulting from the incorrect use of Registry Editor can be solved. Use
Registry Editor at your own risk.

For information about how to edit the registry, view the "Changing Keys And
Values" Help topic in Registry Editor (Regedit.exe) or the "Add and Delete
Information in the Registry" and "Edit Registry Data" Help topics in
Regedt32.exe. Note that you should back up the registry before you edit it.

To tune the connector, perform the following steps:

1. Start Registry Editor (Regedt32.exe), and go to the following subkey:

      HKEY_LOCAL_MACHINE\System\CurrentControlSet
      \Services\Legacy Mail Connector\Parameters

   NOTE: The above registry key is one path; it has been wrapped for readability.

2. From the Edit menu, click Add Value and add the following information:

   QueueInqueueLimit REG_SZ (value not to exceed 200)
   QueueLanMailbagLimit REG_SZ (value not to exceed 200)
   QueueLanPoLimit REG_SZ (value not to exceed 200)

   NOTE: Microsoft has not seen significant improvement when any of these values
   exceeds 200. Microsoft recommends a maximum setting of 200.

3. Quit Registry Editor and restart your computer.

By default, these values are coded into the service and set to 50. Adding these
values overrides the defaults. Administrators running the PCMTA in a large
legacy mail environment can take advantage of these settings and increase
throughput.

Additional query words: XFOR, performance, tune, PCMTA, MSMI

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Keywords          :  
Technology        : kbExchangeSearch kbExchange500 kbExchange400 kbZNotKeyword2
Version           : WinNT:4.0,5.0

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