Note that INITGUID should only be done from one cpp file. It will make errors if you do it in more than one, or do it in a header that is included in more than one.

Anyway, to the thread-stealing anonymous poster...

Extern "C" tells the C++ compiler to use C linkage for functions declared inside that block. If you really understand that you won''t have any problems.

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How To Ask Questions The Smart Way | Google can help with your question | Search MSDN for help with standard C or Windows functions