Finally found how to do it ! #include <Constants.au3> #include <WinAPISysWin.au3> #include <WinAPIError.au3> #include <WinAPIConv.au3> _Main () Func _Main () Local $ctrl_handle Run ("notepad.exe") Local $hWnd = WinWaitActive ("[CLASS:Notepad]", "") Local $tPoint = DllStructCreate($tagPOINT) DllStructSetData($tPoint, "X", 500) DllStructSetData($tPoint, "Y", 500) _