I am receiving the following error when processing incoming mail for one user.

MicroSoft gives the following information:

Cause: A forward loop was detected by the categorizer. This is a common
hosting configuration problem caused when someone uses the provisioning tool
to create a contact in one organization unit and creates a user in a
different organization user that share the same e-mail address.   
Solution: Verify that you do not have a user in organizational unit and a
contact in a different organizational unit that have the same e-mail address.


My problem is that as far as I can tell I have only one organization unit
with 5 users in it, and the user that this is happening for has forwarding
set to NONE on the delivery options page.

Exchange 2003 / 2000 Help
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