No, the mailto syntax doesn't support that.

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Sue Mosher, Outlook MVP
Outlook and Exchange solutions at http://www.slipstick.com
Author of
Microsoft Outlook Programming: Jumpstart
for Administrators, Power Users, and Developers
http://www.slipstick.com/books/jumpstart.htm
> I am trying to automatically set the Category on an email
> in Outlook in the same way as I can use "&body" for the
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>
> L.