Open two encoder sessions with one D3D device.

I use one D3D device to open two encoder sessions, everything is ok, but when i try to use NvEncRegisterResource to do D3D surface register, only one encoder session can success, another one call NvEncRegisterResource success, but the returned registeredResource is zero.
Does anyone know how to solve this problem? Many thanks.

This issue is specific to DX9 driver and has been fixed in latest driver R384. Please try the driver 384.76 ( and let us know if you still encounter the issue.