I am using Visual C++ 9.0 2008 Express Edition with the pre-built boost libraries ver 1.35.0 for Windows . I am using the date_time functions from boost. Everything works fine till i decided to print the date objects through the to_simple_string(date) function . I receive the below linker errors . Can you guys advise me whats wrong ? public: char const * __clrcall boost::gregorian::greg_month::as_long_string(void)const " (?as_long_string@greg_month@gregorian@boost@@$$FQBMPBDXZ) referenced in function "public: static class std::basic_ostream<char,struct std::char_traits<char> > & __clrcall boost::date_time::month_formatter<class boost::gregorian::greg_month,class boost::date_time::iso_format<char>,char>::format_month(class boost::gregorian::greg_month const &,class std::basic_ostream<char,struct std::char_traits<char> > &)" (?format_month@?$month_formatter@Vgreg_month @gregorian@boost@@V?$iso_format@D@date_time@3@D@date_time@boost@ @$$FSMAAV?$basic_ostream@DU?$char_traits@D@std@@@std@ @ABVgreg_month@gregorian@3@AAV45@@Z) 1>ADONET_Example.obj : error LNK2028: unresolved token (0A00007D) "public: char const * __clrcall boost::gregorian::greg_month::as_short_string(void)const " (?as_short_string@greg_month@gregorian@boost@@$$FQBMPBDXZ) referenced in function "public: static class std::basic_ostream<char,struct std::char_traits<char> > & __clrcall boost::date_time::month_formatter<class boost::gregorian::greg_month,class boost::date_time::iso_format<char>,char>::format_month(class boost::gregorian::greg_month const &,class std::basic_ostream<char,struct std::char_traits<char> > &)" (?format_month@?$month_formatter@Vgreg_month @gregorian@boost@@V?$iso_format@D@date_time@3@D@date_time@boost@ @$$FSMAAV?$basic_ostream@DU?$char_traits@D@std@@@std@ @ABVgreg_month@gregorian@3@AAV45@@Z) 1>ADONET_Example.obj : error LNK2019: unresolved external symbol "public: char const * __clrcall boost::gregorian::greg_month::as_long_string(void)const " (?as_long_string@greg_month@gregorian@boost@@$$FQBMPBDXZ) referenced in function "public: static class std::basic_ostream<char,struct std::char_traits<char> > & __clrcall boost::date_time::month_formatter<class boost::gregorian::greg_month,class boost::date_time::iso_format<char>,char>::format_month(class boost::gregorian::greg_month const &,class std::basic_ostream<char,struct std::char_traits<char> > &)" (?format_month@?$month_formatter@Vgreg_month @gregorian@boost@@V?$iso_format@D@date_time@3@D@date_time@boost@ @$$FSMAAV?$basic_ostream@DU?$char_traits@D@std@@@std@ @ABVgreg_month@gregorian@3@AAV45@@Z) 1>ADONET_Example.obj : error LNK2019: unresolved external symbol "public: char const * __clrcall boost::gregorian::greg_month::as_short_string(void)const " (?as_short_string@greg_month@gregorian@boost@@$$FQBMPBDXZ) referenced in function "public: static class std::basic_ostream<char,struct std::char_traits<char> > & __clrcall boost::date_time::month_formatter<class boost::gregorian::greg_month,class boost::date_time::iso_format<char>,char>::format_month(class boost::gregorian::greg_month const &,class std::basic_ostream<char,struct std::char_traits<char> > &)" (?format_month@?$month_formatter@Vgreg_month @gregorian@boost@@V?$iso_format@D@date_time@3@D@date_time@boost@ @$$FSMAAV?$basic_ostream@DU?$char_traits@D@std@@@std@ @ABVgreg_month@gregorian@3@AAV45@@Z) 1>D:\Profiles\g18244\My Documents\Visual Studio 2008\Projects\DataSet\Debug\ADONET_Example.exe : fatal error LNK1120: 4 unresolved externals