I have got a E_NOTIMPL return
Here is my code

Code:
GUID clsid;
GUID iid;
IUnknown*pUnknown=0;
HRESULT hres=IIDFromString(L"xxx",&clsid); //S_OK
hres=IIDFromString(L"xxx",&iid); //S_OK

hres=CoCreateInstance(clsid,0,CLSCTX_INPROC_SERVER,iid,(LPVOID*)&pUnknown); // this fails
Thanks