::GetCursorPos fail (with Access Denied)

    case WM\_SETCURSOR:
        if \(LoWord\(lParam\) == HTCLIENT\) \{
            if \(inDragDrop == ddDragging\) \{
                DisplayCursor\(Window::cursorUp\);
            \} else \{
                // Display regular \(drag\) cursor over selection
                POINT pt;
                if \(0 \!= ::GetCursorPos\(&pt\)\) \{
                    ::ScreenToClient\(MainHWND\(\), &pt\);
                    if \(PointInSelMargin\(Point\(pt.x, pt.y\)\)\) \{
                        DisplayCursor\(GetMarginCursor\(Point\(pt.x, pt.y\)\)\);
                    \} else if \(PointInSelection\(Point\(pt.x, pt.y\)\) && \!SelectionEmpty\(\)\) \{
                        DisplayCursor\(Window::cursorArrow\);
                    \} else if \(PointIsHotspot\(Point\(pt.x, pt.y\)\)\) \{
                        DisplayCursor\(Window::cursorHand\);
                    \} else \{
                        DisplayCursor\(Window::cursorText\);
                    \}
                \}
            \}
            return TRUE;
        \} else \{
            return ::DefWindowProc\(MainHWND\(\), iMessage, wParam, lParam\);
        \}