OpenGL, Windows 2000 and Visual C++ 6.0

OpenGL application compile with Visual C++ 6.0 when I am running under windows 2000 ?
The same application was compiled for Linux and Win98 but strangly not for windows 2000.
When I compile I get an error from gl.h file with the WINGDIAPI macro.
Can anyone help me ?

Thanks in advance

The right question for the incomplete original question above is:

Why do I get an error when I compile my OpenGL App with Visual C++ 6.0 under windows 2000 ?
The compiler returns an error in the gl.h file:
error C2501: ‘WINGDIAPI’ : missing storage-class or type specifiers

How can I overcome this drawback ?

thanks again

Not positive on this because I havent coded gl in windows for a while, but make sure you are including windows.h before gl.h, because gl.h uses windows defined constants.

Old GLman