Here is what I'm trying to do: boost::thread_group threadGroup; for( ; port_min <= port_max; ++port_min ) { threadGroup.add_thread(new boost::thread(boost::bind(CCUThread, port_min, strategy))); } I am getting the following error: error LNK2001: unresolved external symbol "void __cdecl boost::assertion_failed(char const *,char const *,char const *,long)" (?assertion_failed@boost@@YAXPBD00J@Z) ..\bin\ccu_simulator.exe : fatal error LNK1120: 1 unresolved externals Is this Boost-related? I found one posting that was somewhat similar on the web, but the user found an error elsewhere, and it shed no light on the situation. I am also getting several other LNK1120 errors that may be related to Boost. I am converting working VS 6.0 (and occasionally 2005) code to VS 2008; this has caused this link error to appear. I also have changed Boost from v. 1.31 to 1.36; whether this affects the above linker errors I do not know. Any help would be appreciated. Last time I posted about a linking error, I received no replies at all, so if someone knows something, please reply. Thanks Again! (-: Sincerely, Joseph Joseph A. Marks PHONE: 612-788-9658 e-mail: josephamarks@yahoo.com