I'm trying to link a win32 console app using program options. I have previously build boost with bjam using MSVS 7.1. My program, which is pretty basic and taken from first.cpp looks something like this: int _tmain(int argc, _TCHAR* argv[]) { try { po::options_description desc("Allowed options"); desc.add_options() ("help", "produce help message") ("set,s", po::value< std::vectorstd::string >(), "Set one or more node values, overriding stored value in config file") ; po::variables_map vm; po::store(po::parse_command_line(argc, argv, desc), vm); po::notify(vm); if (vm.count("help")) { std::cout << desc << "\n"; } [snip] The program is compiled as _UNICODE. It seems to compile ok, though I get the following warnings: ..\API\inc\boost\program_options\errors.hpp(21) : warning C4275: non dll-interface class 'std::logic_error' used as base for dll-interface class 'boost::program_options::error' C:\Program Files\Microsoft Visual Studio .NET 2003\Vc7\include\stdexcept(14) : see declaration of 'std::logic_error' ..\API\inc\boost\program_options\errors.hpp(21) : see declaration of 'boost::program_options::error' ..\API\inc\boost\program_options\variables_map.hpp(130) : warning C4273: 'boost::program_options::store' : inconsistent dll linkage ..\API\inc\boost\program_options\variables_map.hpp(138) : warning C4273: 'boost::program_options::store' : inconsistent dll linkage But then I get linker errors, like this: NwEngine.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: __thiscall boost::program_options::basic_parsed_options<unsigned short>::~basic_parsed_options<unsigned short>(void)" (__imp_??1?$basic_parsed_options@G@program_options@boost@@QAE@XZ) referenced in function _wmain I have the following lib files in my lib path: boost_program_options-vc71-mt-1_33_1.lib boost_program_options-vc71-mt-gd-1_33_1.lib libboost_program_options-vc71-mt-1_33_1.lib libboost_program_options-vc71-mt-gd-1_33_1.lib libboost_program_options-vc71-mt-s-1_33_1.lib libboost_program_options-vc71-mt-sgd-1_33_1.lib Am I supposed to do something special to link to them? I was under the impression that it worked similar to boost regex and auto-linked. Thanks, Scott