Hi, below are all messages from compiler. There aren't "config_file.cpp:145", so patch you applied works. Regards, Janusz C:/CPP/MINGW/include/c++/3.3.1/bits/basic_ios.h: In instantiation of `std::basic_ios<wchar_t, std::char_traits<wchar_t> >': d:/sources/boost/boost/shared_ptr.hpp:138: instantiated from `std::basic_istream<wchar_t, std::char_traits<wchar_t> >' d:/sources/boost/boost/shared_ptr.hpp:138: instantiated from `boost::shared_ptr<T>::shared_ptr(Y*, D) [with Y = std::basic_istream<wchar_t, std::char_traits<wchar_t> >, D = boost::program_options::detail::null_deleter, T = std::basic_istream<wchar_t, std::char_traits<wchar_t> >]' d:/sources/boost/boost/shared_ptr.hpp:243: instantiated from `void boost::shared_ptr<T>::reset(Y*, D) [with Y = std::basic_istream<wchar_t, std::char_traits<wchar_t> >, D = boost::program_options::detail::null_deleter, T = std::basic_istream<wchar_t, std::char_traits<wchar_t> >]' d:/sources/boost/boost/program_options/detail/config_file.hpp:132: instantiated from `boost::program_options::detail::basic_config_file_iterator<charT>::basic_co nfig_file_iterator(std::basic_istream<charT, std::char_traits<_CharT> >&, const std::set<std::string, std::less<std::string>, std::allocator<std::string> >&) [with charT = wchar_t]' d:/sources/boost/libs/program_options/src/parsers.cpp:255: instantiated from `boost::program_options::basic_parsed_options<charT> boost::program_options::parse_config_file(std::basic_istream<charT, std::char_traits<_CharT> >&, const boost::program_options::options_description&) [with charT = wchar_t]' d:/sources/boost/libs/program_options/src/parsers.cpp:270: instantiated from here C:/CPP/MINGW/include/c++/3.3.1/bits/basic_ios.h:67: error: no type named ` pos_type' in `struct std::char_traits<wchar_t>' C:/CPP/MINGW/include/c++/3.3.1/istream: In instantiation of `std::basic_istream<wchar_t, std::char_traits<wchar_t> >': d:/sources/boost/boost/shared_ptr.hpp:138: instantiated from `boost::shared_ptr<T>::shared_ptr(Y*, D) [with Y = std::basic_istream<wchar_t, std::char_traits<wchar_t> >, D = boost::program_options::detail::null_deleter, T = std::basic_istream<wchar_t, std::char_traits<wchar_t> >]' d:/sources/boost/boost/shared_ptr.hpp:243: instantiated from `void boost::shared_ptr<T>::reset(Y*, D) [with Y = std::basic_istream<wchar_t, std::char_traits<wchar_t> >, D = boost::program_options::detail::null_deleter, T = std::basic_istream<wchar_t, std::char_traits<wchar_t> >]' d:/sources/boost/boost/program_options/detail/config_file.hpp:132: instantiated from `boost::program_options::detail::basic_config_file_iterator<charT>::basic_co nfig_file_iterator(std::basic_istream<charT, std::char_traits<_CharT> >&, const std::set<std::string, std::less<std::string>, std::allocator<std::string> >&) [with charT = wchar_t]' d:/sources/boost/libs/program_options/src/parsers.cpp:255: instantiated from `boost::program_options::basic_parsed_options<charT> boost::program_options::parse_config_file(std::basic_istream<charT, std::char_traits<_CharT> >&, const boost::program_options::options_description&) [with charT = wchar_t]' d:/sources/boost/libs/program_options/src/parsers.cpp:270: instantiated from here C:/CPP/MINGW/include/c++/3.3.1/istream:64: error: no type named `pos_type' in ` struct std::char_traits<wchar_t>' C:/CPP/MINGW/include/c++/3.3.1/bits/istream.tcc:944: error: no type named ` pos_type' in `struct std::char_traits<wchar_t>' C:/CPP/MINGW/include/c++/3.3.1/bits/istream.tcc:957: error: no type named ` pos_type' in `struct std::char_traits<wchar_t>' d:/sources/boost/libs/program_options/src/utf8_codecvt_facet.cpp: In member function `virtual std::codecvt_base::result boost::program_options::detail::utf8_codecvt_facet_wchar_t::do_out(mbstate_t &, const wchar_t*, const wchar_t*, const wchar_t*&, char*, char*, char*&) const ': d:/sources/boost/libs/program_options/src/utf8_codecvt_facet.cpp:115: warning: comparison is always false due to limited range of data type d:/sources/boost/libs/program_options/src/utf8_codecvt_facet.cpp: In function ` int <unnamed>::get_cont_octet_out_count_impl(wchar_t) [with unsigned int s = 4]': d:/sources/boost/libs/program_options/src/utf8_codecvt_facet.cpp:223: warning: comparison is always true due to limited range of data type d:/sources/boost/libs/program_options/src/utf8_codecvt_facet.cpp:226: warning: comparison is always true due to limited range of data type d:/sources/boost/libs/program_options/src/utf8_codecvt_facet.cpp:229: warning: comparison is always true due to limited range of data type