Hi, I have an application using Boost.Filesystem, Boost.Thread and others, that I am building on Windows XP using MSVC8, STLPort and Boost 1.39.0. I have built Boost using Boost Jam 3.1.17 and STLPort. Using the MSVC native STL I get no errors and everything runs well, but with the STL version, I have four linker errors; all from Boost.Filesystem. Has anyone come across this problem before and found a solution, or give me a clue what might be wrong? Many thanks -- Craig 1>fsdatasource.obj : error LNK2019: unresolved external symbol "class boost::filesystem::file_status __cdecl boost::filesystem::detail::status_api(class stlpd_std::basic_string const &,class boost::system::error_code &)" (?status_api@detail@filesystem@boost@@YA?AVfile_status@23@ABV?$basic_string@ DV?$char_traits@D@stlpd_std@@V?$allocator@D@2@@stlpd_std@@AAVerror_code@syst em@3@@Z) referenced in function "bool __cdecl boost::filesystem::is_directory,struct boost::filesystem::path_traits> >(class boost::filesystem::basic_path,struct boost::filesystem::path_traits> const &)" (??$is_directory@V?$basic_path@V?$basic_string@DV?$char_traits@D@stlpd_std@@ V?$allocator@D@2@@stlpd_std@@Upath_traits@filesystem@boost@@@filesystem@boos t@@@filesystem@boost@@YA_NABV?$basic_path@V?$basic_string@DV?$char_traits@D@ stlpd_std@@V?$allocator@D@2@@stlpd_std@@Upath_traits@filesystem@boost@@@01@@ Z) 1>fsdatasource.obj : error LNK2019: unresolved external symbol "class boost::system::error_code __cdecl boost::filesystem::detail::dir_itr_increment(void * &,class stlpd_std::basic_string &,class boost::filesystem::file_status &,class boost::filesystem::file_status &)" (?dir_itr_increment@detail@filesystem@boost@@YA?AVerror_code@system@3@AAPAXA AV?$basic_string@DV?$char_traits@D@stlpd_std@@V?$allocator@D@2@@stlpd_std@@A AVfile_status@23@2@Z) referenced in function "private: void __thiscall boost::filesystem::basic_directory_iterator,struct boost::filesystem::path_traits> >::increment(void)" (?increment@?$basic_directory_iterator@V?$basic_path@V?$basic_string@DV?$cha r_traits@D@stlpd_std@@V?$allocator@D@2@@stlpd_std@@Upath_traits@filesystem@b oost@@@filesystem@boost@@@filesystem@boost@@AAEXXZ) 1>fsdatasource.obj : error LNK2019: unresolved external symbol "class boost::system::error_code __cdecl boost::filesystem::detail::dir_itr_first(void * &,class stlpd_std::basic_string const &,class stlpd_std::basic_string &,class boost::filesystem::file_status &,class boost::filesystem::file_status &)" (?dir_itr_first@detail@filesystem@boost@@YA?AVerror_code@system@3@AAPAXABV?$ basic_string@DV?$char_traits@D@stlpd_std@@V?$allocator@D@2@@stlpd_std@@AAV67 @AAVfile_status@23@3@Z) referenced in function "private: class boost::system::error_code __thiscall boost::filesystem::basic_directory_iterator,struct boost::filesystem::path_traits> >::m_init(class boost::filesystem::basic_path,struct boost::filesystem::path_traits> const &)" (?m_init@?$basic_directory_iterator@V?$basic_path@V?$basic_string@DV?$char_t raits@D@stlpd_std@@V?$allocator@D@2@@stlpd_std@@Upath_traits@filesystem@boos t@@@filesystem@boost@@@filesystem@boost@@AAE?AVerror_code@system@3@ABV?$basi c_path@V?$basic_string@DV?$char_traits@D@stlpd_std@@V?$allocator@D@2@@stlpd_ std@@Upath_traits@filesystem@boost@@@23@@Z) 1>fsdatasource.obj : error LNK2019: unresolved external symbol "class boost::system::error_code __cdecl boost::filesystem::detail::remove_api(class stlpd_std::basic_string const &)" (?remove_api@detail@filesystem@boost@@YA?AVerror_code@system@3@ABV?$basic_st ring@DV?$char_traits@D@stlpd_std@@V?$allocator@D@2@@stlpd_std@@@Z) referenced in function "bool __cdecl boost::filesystem::detail::remove_aux,struct boost::filesystem::path_traits> >(class boost::filesystem::basic_path,struct boost::filesystem::path_traits> const &,class boost::filesystem::file_status)" (??$remove_aux@V?$basic_path@V?$basic_string@DV?$char_traits@D@stlpd_std@@V? $allocator@D@2@@stlpd_std@@Upath_traits@filesystem@boost@@@filesystem@boost@ @@detail@filesystem@boost@@YA_NABV?$basic_path@V?$basic_string@DV?$char_trai ts@D@stlpd_std@@V?$allocator@D@2@@stlpd_std@@Upath_traits@filesystem@boost@@ @12@Vfile_status@12@@Z)