XCON: Configuring MTA TCP/IP Port # for X.400 and RPC Listens (161931)

MORE INFORMATION

By default, the Exchange Server MTA uses TCP/IP port 102 to communicate with other X.400 MTAs. For example, if two Exchange Server sites are connected by an X.400 Connector with a TCP/IP MTA stack, both MTAs communicate over port 102 by default. However, you can configure this port number if you add the following registry value: This case-sensitive registry value is a DWORD value type, and does not exist by default. To add the registry value:

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. Start Registry Editor (Regedt32.exe).
2. Locate the following key in the registry:

   HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSExchangeMTA\Parameters

3. On the Edit menu, click Add Value, and then add the following case-sensitive registry value:

   Value Name: RFC1006 Port Number
   Data Type: REG_DWORD
   Value: The decimal value for the port that you want to use.

4. Quit Registry Editor.

If the RFC1006 Port Number registry value does not exist in the registry, the Exchange Server MTA assumes a value of 102 for this setting, and expects all X.400 MTA communication to occur over port 102 when you use a TCP/IP MTA stack. All MTAs that communicate with each other over X.400 need to use the same TCP/IP port number.

An additional registry setting allows you to configure the MTA to listen to RPCs on a specific port number. You do not need to configure all of the Exchange Server MTAs to listen for RPC communication on the same port. RPC communication relies on the end-point mapper to relay the appropriate port number, so that further communication can then be achieved by going directly to the port number that the end-point mapper reports for a specific server. You can examine this behavior by using a network sniffer such as Network Monitor to monitor the RPC communication between two MTAs.

The following registry value determines the TCP/IP port that a given MTA uses to listen for RPC communication: This case-sensitive registry value is a DWORD value-type and does not exist by default. To add the registry value:

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. Start Registry Editor (Regedt32.exe).
2. Locate the following key in the registry:

   HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSExchangeMTA\Parameters

3. On the Edit menu, click Add Value, and then add the following case-sensitive registry value:

   Value Name: TCP/IP port for RPC listens
   Data Type: REG_DWORD
   Value: The decimal value for the port that you want to use.

4. Quit Registry Editor.

The MTA does not read either of these two registry values dynamically. Therefore, after you make a change to one of these registry settings, you must stop and restart the MTA before the change takes effect.

For additional information about the ramifications and guidelines for staticport assignment of Exchange services, click the article number below to view the article in the Microsoft Knowledge Base: These two features are available in Exchange Server version 4.0 Service Pack 4 and in Exchange Server version 5.0.