In another memo, I explained that the XP DDK comes with its own compiler and linker. This is, interestingly enough, an early version of the MSVC++ V7 compiler. Cool, eh?
When building drivers with the XP DDK, you must use (at least) the version of the compiler supplied with the DDK. You can not use MSVC++ V6. It's not supported. Plus, the libraries and DLLs on the DDK are all built with the compiler that's in the DDK. There's no reason to expect the (older) V6 compiler to properly work with these components built with the new compiler.