hi, i compiled boost for windows using the msvc-8.0 and msvc-8.0_64 targets. the following code works perfectly on debug builds but crashes on the marked line in x64 mode and goes into an infinite loop in x86 mode. i used visual studio 2005 with and without service pack 1 and even tried the head version of boost. everytime the crash occurs. int main(int argc, char **argv) { int width; int height; try { boost::program_options::options_description cmd_options("program options"); cmd_options.add_options() ("help", "show this help message") ("width", boost::program_options::value<int>(&width)->default_value(1024), "output width") ("height", boost::program_options::value<int>(&height)->default_value(640), "output height"); boost::program_options::variables_map command_line; ***> boost::program_options::store(boost::program_options::parse_command_line(argc, argv, cmd_options), command_line); boost::program_options::notify(command_line); if (command_line.count("help")) { std::cout << "usage: " << std::endl; std::cout << cmd_options; return (0); } winx = width; winy = height; } catch (std::exception& e) { std::cout << e.what() << std::endl; return (-1); } } thanks for your help -chris -- Christopher Lux | | Bauhaus University Weimar | Faculty of Media - Virtual Reality Systems Group