I JUST DOWNLOADED LIMEWIRE A WEEK AGO AND IT WORKED FINE UNTIL TODAY. I CHECKED UNDER THE START MENU ON RUNNING, TO SEE IF MY COMPUTER SAID "GNUTELLA OK," AND IT SAID "OK". BUT WHEN I TRY TO CONNECT IT ONLY FLASHES GREEN FOR A SECOND THEN BACK TO RED. ALSO, WHAT IS A FIREWALL, AND HOW DO I GET IN TO IT OR UNINSTALL OR INSTALL A FIREWALL. PLEASE HELP.