NVIDIA H.264 Encoder Media Foundation Transform’s REGDB_E_CLASSNOTREG

For already years Nvidia’s H.264 video encoder Media Foundation Transform has been broken giving REGDB_E_CLASSNOTREG “Class not registered” failure in certain circumstances, like main display is not the one connected to Nvidia video adapter.

As simple as this:

CoInitialize(NULL);
MFStartup(MF_VERSION);
class __declspec(uuid("{60F44560-5A20-4857-BFEF-D29773CB8040}")) CFoo; // NVIDIA H.264 Encoder MFT
CComPtr<IMFTransform> pTransform;
const HRESULT nCoCreateInstanceResult = pTransform.CoCreateInstance(__uuidof(CFoo));
// NOTE: nCoCreateInstanceResult is 0x80040154 REGDB_E_CLASSNOTREG

The COM server itself is, of course, present and registered properly via their nvEncMFTH264.dll, it’s just broken inside. Being called straightforwardly via IClassFactory.CreateInstance it gives 0x8000FFFF E_UNEXPECTED “Catastrophic Failure”, and so it also fails in Media Foundation API scenarios.

This is absolutely not fun, Nvidia!