Outlook Express 6 Forwarding FPs
Messages forwarded automatically by a Message Rule in Microsoft Outlook Express 6 may be marked as junk mail because of a bug in Outlook Express.
If the action of a Message Rule is set to Forward messages, Outlook Express correctly changes the From: header of the forwarded message but does not correctly generate a new message ID. If the domain name in the message ID does not match the domain name in the From: header, the message may be marked as junk (a false positive), as this mismatch violates RFC 2822.
This is a bug in Outlook Express, and there is no known workaround.
This issue has been filed as a documentation bug. For further details:
[http://bugzilla.spamassassin.org/show_bug.cgi?id=2072]