Help Me Exorcise My Internet!

[Sirbomber]

My internet is out to get me now... It's up to all of you to help me!
Okay, here's what's happening:

My computer is saying I have an active, working internet connection. But whenever I try to access the internet, it doesn't work! Other computers on different connections can access the internet without any problems at all. I've tried updating something, using Internet Explorer, and loading Hamachi. None of it did anything, although the aforementioned update got up to 5% and suddenly stopped with a generic "failed to connect" error. Not even Outpost 2 can defeat this mechanical menace!

What I've tried:
Restarted computer (several times)
Restarted router (twice)
Unplugged internet cable, put it back in (once)
Virus/spyware scan
Fiddled with router settings (The only thing IE can still do)

What I Thought of But Didn't Do:
Try using a different cable (I hate messing with cables, but if I have no choice...)

If you can help me, that'd be great. I'm ready to try almost anything now. But, hurry up, because I don't know how long this old thing will hold out...

[BlackBox]

So are you connected to the same cable / DSL modem as your other computers? or using a completely different internet connection?

[Sirbomber]

Woot! Mez fixed it!

Never mind.

[Mez]

The joys of corrupt network stacks