I have two computers, one with XP with SP newly installed, the other with XP with SP2 upgrade. They are wirelessly coonetced via an ADSL router. The newer machine has connected faultlessly since installation. The latter, after problems, eventually connected and then disconnected after a few hours despite showing good communication with the router. My installer, who is now geting grey hairs, changed the network card - no good - then changed the router. Magical for a few hours, then Windows will not connect - again. Norton IS has been disabled (Norton AV still there of course). Previous threads indicate it might be solved by turning router on and off but this seems a less than perfect solution. Another thread blames XP firewall.