Well, with the firewall in front of the globe, it explains that you can't connect.....
That you haven't changed anything, I believe you, however, since the last update of XP from MS, some things might have changed by itself.
Besides, the router you mentioned has a built-in firewall (according to the infro I googled).
http://www.speedtouch.co.uk/prod510s...menuCurrPos=2.
That means you've to configurate your XP firewall and the one in the router:
Read here on how to do that:
http://www.gnutellaforums.com/showthread.php?t=51361

A tip from me, after you've configurated the firewall, give LW some time to settle down. It can sometimes last between 5-45 minutes until the brickwall disappears (later on it goes faster, maybe 30 sec. - 1 min.)

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