Can't connect to the internet

[AFurryReptile]

I have a computer that, up until this morning, could connect to the internet via a broadband router. Now, it won't connect at all, and when I try to repair, it cannot assign a new IP address.

I've tried new Ethernet cables, and tried connecting directly to the modem instead of a router, but nothing works. My only thought is that it is something wrong with the computer, but I don't know what.

Can anyone help?

 

[JackMDS]

The way to assess the Network setting of a computer is described here, http://www.ezlan.net/debug.html

 

[Fullmetal Chocobo]

I had this same thing happen, and it seems to be an issue (albeit rather rare one) with Nvidia NICs. I fixed it by turning off the computer, unplugging the cat5 cable, then unplugged the power cable to the computer's power supply, waited a few minutes, then plugged them in again in reverse order. Hope it helps, and good luck.