there is no /tmp directory on windows. I use this for sessions when developing on windows. It has the benefit that if you forget to remove it when you upload it online, it still works.
if ($PHP_OS == 'WIN32') {
session_save_path("c:/windows/temp");
}
session_start();
You may want to check and make sure I have that environment variable correct. ($PHP_OS). I am working from memory here. Youi also need to make sure there is a c:windows/temp directory as well. Should be, but I am not on windows 2000, so I don't know if it is still there in that version. You may want to use echo $PHP_OS; first, to make sure the string returned is "WIN32".