Outlook doesn't support importing to a custom form. You'd have to write
custom code or use a third-party application. See
http://www.outlookcode.com/d/customimport.htm.

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Sue Mosher, Outlook MVP
Author of
Microsoft Outlook Programming - Jumpstart for
Administrators, Power Users, and Developers
http://www.outlookcode.com/jumpstart.aspx
>I have created a custom form to import sales leads into a separate folder
>in
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> under "user defined fields" as I was designing the form. How do I get the
> custom fields into the "map custom fields" box.