If you have Outlook 2000 or later, you can make a registry change to
substitute your custom form for the default form. See
http://www.outlookcode.com/d/newdefaultform.htm#changedefault . Note that it
doesn't work completely for message forms in Outlook 2003.

Signature
Sue Mosher, Outlook MVP
Author of
Microsoft Outlook Programming - Jumpstart for
Administrators, Power Users, and Developers
http://www.outlookcode.com/jumpstart.aspx
>I can figure out how to add a custom field to a contact form but it doesn't
> update to the existing contacts.