Ensure that the point argument is relative to the map instance. You can easily do this by using the method:
myElement.TransformToVisual(myMap).Transform(myPoint);
Where myElement is the element the screen coordinates are relative to. You can use "System.Windows.Application.Current.RootVisual" if you want to use coordinates relative to the entire control.
Parameters
- point
- Point to convert.
Return Value
Map coordinateTarget Platforms: Windows XP Professional, Windows Server 2003 family, Windows Vista, Windows Server 2008 family, Windows 7, Windows 8