Ah ... that's a starting point to your problem. Even M$ recommend against running XP firewall with any others as do all other firewall producers. Disable one or the other (better to disable XP firewall.) Then see if the brick wall goes away. If not, see http://www.gnutellaforums.com/showth...ht=#post222774
Running both defender & NFW should be fine. (BTW running 2 firewalls simultaneously actually leads to less security, not more! They will clash in their operations.)