SMTP: Err Msg: 503 Bad Command Sequence (99855)


The information in this article applies to:

  • Microsoft Mail Gateway to SMTP 2.1
  • Microsoft Mail Gateway to SMTP 3.0
This article was previously published under Q99855

SYMPTOMS

Versions 2.1 and 3.0 of Microsoft Mail Gateway to SMTP may display this error message:
"503 Bad command sequence"

CAUSE

This error message indicates that an SMTP command was received out of sequence. After sending this error message to the calling host, the SMTP Gateway waits for another command.

RESOLUTION

Check the SMTPGATE.LOG file to find the offending command that caused the error. Then, contact the sending host to determine why the command was given.
Modification Type:MajorLast Reviewed:10/2/2003
Keywords:KB99855
©2003 Microsoft Corporation. All rights reserved.