Hi there, I am writing a DLL under Windows with MSVC 2005. In my project, boost:regex is involved. I do nothing but include the following in my stdafx.h #include <boost/regex.hpp> #include <boost/regex/v4/match_flags.hpp> #include <boost/scoped_ptr.hpp> #include <boost/compressed_pair.hpp> #include <boost/format.hpp> #include <boost/algorithm/string/regex.hpp> #include <boost/algorithm/string/regex_find_format.hpp> #include <boost/algorithm/string/replace.hpp> #include <boost/algorithm/string/split.hpp> #include <boost/algorithm/string.hpp> #include <boost/algorithm/string_regex.hpp> #include <boost/algorithm/string/trim.hpp> #include <fstream> #include <sstream> #include <string> #include <vector> it is all right to complie the project once I specify the path of the library of boost::regex. I found there are librarys in the directory libboost_regex-vc80-mt-s-1_33_1.lib and libboost_regex-vc80-mt-s.lib I wonder what's different between these two librarys? Which one should I used to develope a DLL? Thanks in advance.