This is my very first experience with Boost. I am actually trying to use the SDTS++ libraries (if anyone is familiar with them) which use Boost. Anyway, I successfully built the library using the Jamfile that was included with the download which looks something like this: lib sdtsxx : ... : <include>$(BOOST_ROOT) <include>$(TOP) <include>. <include>$(TOP)/Windows # to get bogus "unistd.h" <rtti>on <exception-handling>on <msvc><*><cflags>-TP # force to compile as C++ <gcc><*><cflags>"-x c++" # force to compile as C++ <gcc><*><define>VECTOR_ITERATOR_POINTER_NOT_EQUIVALENT : debug release ; However, what I need is for the library to be a dll. So I changed the Jamfile to look something like this: SOURCES = ...; dll sdtsxx : $(SOURCES) : <include>$(BOOST_ROOT) <include>$(TOP) <include>. <include>$(TOP)/Windows # to get bogus "unistd.h" <rtti>on <exception-handling>on <msvc><*><cflags>-TP # force to compile as C++ <gcc><*><cflags>"-x c++" # force to compile as C++ <gcc><*><define>VECTOR_ITERATOR_POINTER_NOT_EQUIVALENT : debug release ; Unfortunately this gives me linking errors like this: sb_Accessor.obj : error LNK2001: unresolved external symbol "public: class boost::filesystem::path __thiscall boost::filesystem::path::branch_path(void)const "(? branch_path@path@filesystem@boost@@QBE?AV123@XZ) Now I don't know that this is a Boost problem or if I should go to the SDTS people. Since the unresolved externals are from the Boost libraries I figured it was a Boost issue. So am I doing something wrong with the Jamfile, or is there a problem with Boost? Or is it something completely different? Oh, I'm using msvc on an XP machine, if that matters... -ms