error c2555

[kalensino]

Help! I am new to the driver library.
My complier environment is VC2008. I only inserted the code "DirectShowLib::InitLibrary(0)" in the InitInstance() , the complier complainted that error C2555: DirectShowLib::IFrameFilterBase::QueryInterface" overriding virtual function return type differs and is not covariant from“IUnknown::QueryInterface."
How can I solve the problem? Thanks.

[kalensino]

Due to my careless, i put the the header file (IATUDSHL.H) in the CxxApp and gotton the error C2555. After puting the IATUDSHL.H into the stdafx.h , the problem was solved.