EDIT: Changing the computer's static IP address seems to have fixed the problem. It seems as if I should move this discussion from LQ to a router forum now.
I've got three computers behind a router, connected to an ADSL internet connection. One of them dual boots Windows XP and OpenSuse 10.0. The other two just run OpenSuse.
This morning, the dual booter's Windows antivirus said that it found a trojan in the Firefox cache. Luckily, it caught it before anything bad happened. The internet wouldn't connect, though, after this. I thought that maybe the antivirus/firewall program (BitDefender) might have locked the internet connection as a safety measure.
The other two computers run fine, internet speed is nice and fast.
So we rebooted into OpenSUSE 10.0, as I was sure that there would be no problem. Still, no luck getting an internet connection.
Here are the different things I've done to see if I could find the problem: rebooted with a Knoppix disc (worked! the internet connection came up without a problem), changed ethernet cables, turned off the firewall (Windows and linux), and switched from static IP to DHCP.
The only thing that works is rebooting with Knoppix.
This is very strange. I'm thinking that it must be something with the router (that's what I'm going to play with right now), but if anybody has any ideas, I'd be very grateful!