Make sure that the XP firewall's off & that you've configured the PC-cillin firewall to allow LW.

Your router has a firewall
Enable UPnP within the router & then choose the UPnP option within LW's tools > options > advanced > firewall config. Wait a little while to see if the brick wall disappears.

If enabling UPnP doesn't help, try port forwarding. Here are the instructions for your router.
http://www.portforward.com/english/r...4/Limewire.htm

Don't forget the step of setting up a static IP (there's a link within those instructions). Remember that LW's listening port, port in the 'manual port forward' box, port forwarded within the router all have to be the same number