You can explicitly restore the display hardware to its original mode by calling the IDirectDraw2::RestoreDisplayMode method. If the display mode was set by calling IDirectDraw2::SetDisplayMode (rather than IDirectDraw::SetDisplayMode) and your application takes the exclusive cooperative level, the original display mode is reset automatically when you set the application's cooperative level back to normal. If you're using the IDirectDraw interface, you must always explicitly restore the display mode.