XCON: X.400 Connector Uses Session Selector on X.400 Connections

• Microsoft Exchange Server, versions 4.0, 5.0, and 5.5

SYMPTOMS

If a Session Selector (S Sel) is defined for an X.400 connection defined with X.410 conformance, communication to foreign X.400 systems may not work properly.

The Windows NT Application Event Log may contain the following entry:

   Event ID: 51
   Source:  MSExchangeMTA

   Description:
   An unknown MTA has attempted to bind. The MTA name in bind is
   <REMOTE MTA NAME>. The MTA presentation address is
   /t:0x44454D4F/n:0x444545392D5443504950,
   Association index: 2018. [MTA XFER-IN 35 42] (14)

CAUSE

Exchange Server incorrectly sends, and expects to receive, a Session Selector (S Sel) on an X.410 conformant connection if defined to do so in the X.400 Connector Stack property pages.

A X.410 conformant connection is configured by choosing 1984 or 1988 X.410 mode in the MTA conformance pane of the Advanced property page for the X.400 Connector.

Exchange should ignore the S selector value for X.410 conformant connections.

RESOLUTION

Do not define X.400 systems with S selector values if X.410 conformant connections will be used. By manipulating the OSI Protocol Information in the Stack Property Page of the X.400 Connector, you may be able to configure the X.400 connector to send an S selector (if necessary), but not to expect one in return.

STATUS

Microsoft has confirmed this to be a problem in Microsoft Exchange Server, version 4.0, 5.0, and 5.5. We are researching this problem in versions 4.0 and 5.0, and will post new information here in the Microsoft Knowledge Base as it becomes available.

A supported fix for version 5.5 is now available, but has not been fully regression-tested and should be applied only to systems experiencing this specific problem. Unless you are severely impacted by this specific problem, Microsoft recommends that you wait for the next Service Pack that contains this fix. Contact Microsoft Technical Support for more information.