Import Libraries ~~~~~~~~~~~~~~~~ These are used with C/C++ languages so that the compiler knows what functions can be found in which DLLs. You need to link the appropriate import library to your source code so that the DLL can be called correctly. Microsoft import libraries ~~~~~~~~~~~~~~~~~~~~~~~~~~ dpwin32.lib dpwin32debug.lib DinkeyChange.lib DinkeyChangeDebug.lib Borland C++ Builder import libraries ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ dpwin32_borland.lib dpwin32debug_borland.lib DinkeyChange_borland.lib DinkeyChangeDebug_borland.lib Dev C++ and MinGW import libraries ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ libdpwin32.a libdpwin32debug.a libDinkeyChange.a libDinkeyChangeDebug.a If you look at the sample code for the relevant language / compiler then it will tell you how to use these import libraries.