Win XP, so did you install SP2? I hope not, you don't need it b/c it was not designed for individual home users! And sp2 reduces connectivity to the net & also changes all your firewall settings back to default.

To configure XP & other firewalls to allow LW acces see here: http://www.limewire.com/english/content/firewalls.shtml (other firewall types are at bottom of page.)