Knowledge Base

The EXPN command is not supported by Exchange Internet Mail Service

Article ID: 175842

Article Last Modified on 10/25/2007


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This article was previously published under Q175842

SUMMARY

The RFC 821 EXPN (expand) command is used to identify and return members of a named mailing list. This option is not supported by the Microsoft Exchange Internet Mail Service. If you attempt to use this command against an Exchange Internet Mail Service via a Telnet session or SMTP client session, you will receive the following error:
Exchange 4.0, 5.0, and 5.5: 502 command not implemented Exchange 2000, 2003: 500 5.3.3 Unrecognized command

STATUS

This behavior is by design.

Additional query words: imc connector XFOR

Keywords: kbinfo KB175842