| DirectX SDK | 
The IDirectInputEffect::GetEffectGuid method retrieves the GUID for the effect represented by the IDirectInputEffect object.
HRESULT GetEffectGuid( LPGUID pguid );
If the method succeeds, the return value is DI_OK.
If the method fails, the return value can be one of the following error values:
| DIERR_INVALIDPARAM | 
| DIERR_NOTINITIALIZED | 
Additional information about the effect can be obtained by passing the GUID to IDirectInputDevice7::GetEffectInfo.
  Windows NT/2000: Requires Windows 2000.
  Windows 95/98: Requires Windows 95 or later. Available as a redistributable for Windows 95.
  Header: Declared in dinput.h.
  Import Library: Use dinput.lib.