Could you please share some code with us? This could shed some light on the problem. The RadContextMenu is not designed to work as a UserControl and we haven't tested the control behavior in such scenario. I would suggest you to refer to our online documentation - http://www.telerik.com/help/wpf/radcontextmenu-how-to-use-radcontextmenu-with-radgridview.html
I hope this helps.
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