Take a look at the UserProperties.Add method.

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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.outlookcode.com/jumpstart.aspx
> Hi
> Dim TaskOutlook As Outlook.TaskItem
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>
> how can i create by user defined fields ?