SYMPTOMS
An Exchange Server computer that is configured to perform MIME Internet X.400 Enhanced Relay (MIXER) address mapping may encapsulate an unknown X.400 address in an SMTP address that is derived from the X.400 address, instead of from the SMTP address of the server. If this unknown X.400 address is the address from which the message was sent, then replies from the Internet are not possible.
For example, if an X.400 user with an O/R address of "c=gb; a=admd; p=prmd; s=sender" sends a message to the Internet by using an Exchange Server MIXER server that has an SMTP proxy address of "mixer.org.com," the SMTP message is generated with the following From line:
"/S=Sender/P=prmd/A=admd/C=GB/"@prmd.admd.gb
The address should be the following:
"/S=Sender/P=prmd/A=admd/C=GB/"@mixer.org.com
Note that this behavior only occurs if the X.400 sender is not in the global address list on the MIXER server. If there is a global address list entry for the user, then the SMTP address from the global address list entry is correctly used.
RESOLUTION
To resolve this problem, obtain the latest service pack for Exchange Server 5.5. For additional information, click the following article number to view the article in the
Microsoft Knowledge Base:
191014 XGEN: How to Obtain the latest Exchange Server 5.5 Service Pack