XCON: X.400 Address Is Given SMTP Address Type If Received Over Connector with MIME Internet X.400 Enhanced Relay Heuristic Set

If you receive a message from a remote X.400 system that is also addressed to another remote X.400 user, the address of the remote X.400 user may be correctly displayed but the address type may be displayed as Simple Mail Transfer Protocol (SMTP). You cannot reply to this other recipient.

This problem can occur if the message entered the organization over an X.400 Connector that has the HEUR_MIXER_TO_SMTP heuristic (0x20000000) set. A logic error in the code causes this X.400 address, which is not resolved against the global address list, to be given the SMTP address type.

A supported fix is now available from Microsoft, but it is only intended to correct the problem that is described in this article. Apply it only to computers that are experiencing this specific problem. This fix may receive additional testing. Therefore, if you are not severely affected by this problem, Microsoft recommends that you wait for the next Microsoft Exchange Server version 5.5 service pack that contains this hotfix.

To resolve this problem immediately, contact Microsoft Product Support Services to obtain the fix. For a complete list of Microsoft Product Support Services phone numbers and information about support costs, visit the following Microsoft Web site:NOTE: In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem. The typical support costs will apply to additional support questions and issues that do not qualify for the specific update in question.

The English version of this fix should have the following file attributes or later:

Component: Message Transfer Agent

Microsoft has confirmed that this is a problem in Microsoft Exchange Server version 5.5 Service Pack 3.