I inherited a substantial amount of code, including a visual studio project that is supposed to (as best as I can tell) build a .lib file. Visual studio says \"... Generating C
I had the same problem, even though I was already using the __declspec(dllexport) function.
Your ProjectName.cpp file needs to #include "ProjectName.h". If you don't include the header file then the functions don't get exported. The DLL builds fine, no errors or warnings (at least in VS2017 15.8), but you don't get a LIB file.
Include the header and boom - LIB file is generated. A rookie mistake I'm sure, but everyone has to start learning somewhere.