The IDirectDraw2::RestoreDisplayMode method resets the mode of the display device hardware for the primary surface to what it was before the IDirectDraw2::SetDisplayMode method was called. Exclusive-level access is required to use this method.
HRESULT RestoreDisplayMode();
If the method succeeds, the return value is DD_OK.
If the method fails, the return value may be one of the following error values:
| DDERR_GENERIC |
| DDERR_INVALIDOBJECT |
| DDERR_INVALIDPARAMS |
| DDERR_LOCKEDSURFACES |
| DDERR_NOEXCLUSIVEMODE |
IDirectDraw2::SetDisplayMode, IDirectDraw2::EnumDisplayModes, IDirectDraw2::SetCooperativeLevel