XCON: Eicon X.25 Limited to Control Block Value of 32 (193323)


The information in this article applies to:

  • Microsoft Exchange Server 4.0
  • Microsoft Exchange Server 5.0
  • Microsoft Exchange Server 5.5
This article was previously published under Q193323
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.

SYMPTOMS

Customers may report that their X.25 connection is no longer working. Symptoms of this behavior can be tracked down with Event Viewer by setting the logging for the diagnostic option "X.400 service" to Medium. This should produce the following event: 
  Event Id: 252
  Source: MSExchangeMTA
  Description: An internal MTA error has occurred.  No supporting stack
               configured for OSI entity : %1\n
Logging will also register another event: 
  Event Id: 9106
  Source: MSExchangeMTA
  Description: An internal MTA error occurred. The X.25 interface
               failed to initialize. Check to make sure the X.25 card
               is started.
When you use Eicon's diagnostics ECMODULE, STATUS X25 shows no "x25listen" application. An Eicon Trace shows only incoming calls, which will be refused right away with Clear code 40 (Call set up, clearing, or registration problem).

CAUSE

Microsoft Exchange Server configured with the Eicon X.25 stack may be set to an incorrect number of control blocks or virtual circuits.

WORKAROUND

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. If you are running Windows NT, you should also update your Emergency Repair Disk (ERD).

  1. Start Registry Editor (Regedt32.exe).
  2. Locate the "Eicon X.25 Connections" value under the following key in the registry: 
          HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MSExchangeMTA
      \Parameters
    NOTE: The above registry key is one path; it has been wrapped for readability.
  3. Verify that this value (DWORD) has NOT been configured for a value greater than 32 decimal. If it has, change the setting to less than 32 decimal. See the More Information section below.
  4. Quit Registry Editor.

MORE INFORMATION

Microsoft Exchange Server configured with the Eicon X.25 stack can only support up to 32 control blocks or virtual circuits. If any more than 32 control blocks are configured, error 9106 will be logged at initialization, and no X.25 functions will be available.
Modification Type:MinorLast Reviewed:4/28/2005
Keywords:kbprb KB193323
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