IDirectInputEffect::Download Method
HRESULT Download()
Return Value
If the method succeeds, the return value is DI_OK or S_FALSE. If the method fails, the return value can be one of the following error values: DIERR_DEVICEFULL, DIERR_EFFECTPLAYING, DIERR_INCOMPLETEEFFECT, DIERR_INPUTLOST, DIERR_INVALIDPARAM, DIERR_NOTEXCLUSIVEACQUIRED, DIERR_NOTINITIALIZED.
If the method returns S_FALSE, the effect has already been downloaded to the device.
It is valid to update an effect while it is playing. The semantics of such an operation are explained in the reference for IDirectInputEffect::SetParameters.