Thanks for all the suggestions. I'm not sure why any firewall software would fundamentally block a wireless connection yet allow the wired network to connect? From memory I just have the XP firewall on in my laptop (it's a low spec machine). I'm pretty sure Ryan's laptop was the same. However fL4t_t1Rz, wireless networks exhibit some strange behaviour at times and it's something to consider.

BrainStop yes, I was connecting directly to the router when I wired the computers to the network. The setup is that it's a Linksys WRT54GS wireless router with a couple of ports for wired connections. I find it hard to believe that the manufacturers would make it hard to get DHCP working for the wired and wireless parts of the network since that's the whole strength of the router and people don't necessarily know how to create subnets when they decide on this kind of setup.

very_unhappy, the reason I was "messing with encryption" is that everything was working for a year with wireless networking (including encryption) set up and functional until Ryan decided to restore Windows back to factory settings. So the WEP keys etc were already in the router. In theory, both my laptop and his should have been able to just connect.

I'm afraid the only web address I tried to connect to by entering the IP was the router homepage ...... I simply didn't have enough time to spend on the problem. I guess I could try getting them to do that and if it does connect, then input new DNS servers. If it didn't, they could ditch encryption altogether till we got a connection and if that still didn't work, then a router reboot. Trouble is, I know if they got it working without encryption they'd probably just not set up WEP after all this