ClientToWindow method
Computes the full size of the browser window when given the specified width and height of the content area.
var retval = InternetExplorer.ClientToWindow();
cx [in, out, ref]
Type: IntegerInteger that specifies the width of the client area. On return, this variable contains the full width required by the browser window.
cy [in, out, ref]
Type: IntegerInteger that specifies the height of the client area. On return, this variable contains the full height required by the browser window.
The WebBrowser object returns an error from this method.
Reference