XCON: Eicon Default Setting Only Allows for Four MTA Associations (174257)



The information in this article applies to:

  • Microsoft Exchange Server 5.5

This article was previously published under Q174257

SYMPTOMS

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.

When you use the Microsoft Exchange X.400 connector over an X.25 card to connect to another system, you may receive the following error messages when you try to open an association to another system:
Event ID: 9102
Source: MSExchangeMTA
Type: Warning
Category: Resource

An X.25 resource limit was reached while attempting to open an association. Connection control block: 3. Logical session number: 0. Error code: 9. [BASE IL EICON RESULT 16 144] (10)

Event ID: 9131
Source: MSExchangeMTA
Type: Information
Category: Field Engineering

An X.25 connection ended normally (hung up). Connection control block:
3.. Logical session number: 0. Return code: 265. [BASE IL EICON WORKER 15 210](10)

Event ID: 9134
Source: MSExchangeMTA
Type: Information
Category: Field Engineering

An X.25 call on was made for address
333130343030303837320000000000000000000000000000000000000000000000000000
000000000000000000000000000000000000000000 on port 1. Connection control
block: 3. Logical session number: 0. Return code: 0. [BASE IL EICON WORKER 15 210] (10)

CAUSE

This problem usually occurs when associations over the X.25 WAN adapter are already open, and the card is simply busy. By default, the Exchange message transfer agent (MTA) attempts to use up to 20 X.25 two-way virtual circuits. With the Eicon WAN adapter, the WAN Services for Windows NT software sets the default two-way virtual circuits to four. Therefore, when the MTA makes four associations the card will no longer accept open associations.

RESOLUTION

To prevent the MTA from attempting to open an association over a busy X.25 card, use of the following two methods:

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.

  1. Change the default two-way virtual circuits value for the MTA from 20 to 4 to reflect the default setting of the Eicon WAN adapter. To do this, edit the Windows NT registry and make the following adjustment:
          HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MSExchangeMTA
          \Parameters
          Eicon X.25 Connections
    						
    Change the default two-way virtual circuits value for the MTA to match the Eicon default of 4 or whatever the Eicon two-way virtual circuits value is set to. -OR-

  2. Use the WAN Services for Windows NT to change the WAN adapter to 20 to match the MTA default value.

Modification Type:MinorLast Reviewed:4/28/2005
Keywords:kbbug KB174257