[Koha] Koha Installation on windows

Dear All, I have installed mysql, perl and then koha for windows. When I run it by typing http://localhost, it give me the following error: ************ Server error! The server encountered an internal error and was unable to complete your request. Error message: couldn't create child process: 720003: opac-main.pl If you think this is a server error, please contact the webmaster. Error 500 localhost 05/26/04 18:58:37 Apache/2.0.49 (Win32) *************************** Can you please assist me resolve this? Kondwani