Here is my scenario,

New external extension dll is created and one method is exported from this dll.
This method is called from silk test script. This method takes one input HWND.
Silk sends this input with call GetHandle() on specific control.
In extension application method, we are trying to get CWnd pointer using call CWnd::FromHandlePermanent()

This call is returns Null poiner which indicates that CWnd object is not attached to handle.

Can anybody tell why i am getting null pointer?