Problem connecting to internet with PC

[nana6]

hello - I hope someone can help me!
I purchased a used computer from my employer. It was "wiped clean", meaning that even the OS was removed (the disks were supplied to us). After getting the unit home, I re-installed the OS (Windows XP Pro, service pack 2).
I then attempted to connect to the internet using a router (Linksys BEFSR41 with 4 ports). My MAC is connected to the router and as you can tell, is working fine. The PC, however, recognizes that it is hooked up to the router, but cannot access the internet.

Obviously I am missing something, just don't know what. I tried the "ping" and provided the IP address for the router, but doing that only gets the following response: Destination host unreachable

I tried advice I saw on this website, just today: Netsh interface set interface name="local area connection" admin=enabled
the response is: An interface with this name is not registered with the router

I am at my wits end, here. very confused and frustrated over this issue. Is there an easy answer? I don't know where to turn.

any advice you can offer is sincerely appreciated!

[AboveTheLogic]

does the light on the router for the port you plugged into light up?

is there more than 1 NIC port on the PC?

[nana6]

The "power" light, "ethernet" lights (2 because I have 2 computers ) and the "internet" lights are all lit up

[nana6]

What is an NIC port? There is only one place on the CPU to insert an ethernet cable

[AboveTheLogic]

by NIC port, I meant thae port where you can insert the ethernet cable

all are lit up, but no connection? sounds like a bad driver or bad NIC to me...

[nana6]

what kind of driver would I need?
is there a way to test the NIC port to see if it is bad?

Thanks so much for your help, thus far

[AboveTheLogic]

you would have to determine what kind of NIC it is

if it is onboard and it is a commercial PC (not home-built), you can probably search on the manufacturer's site by model number

if its not a commercial PC, you'd need to look at the motherboard to get the model and search the motherboard manufacturer's site

if its not an on-board NIC (meaning that there is a PCI card), then you'll need to look at the card and search the manufacturer's site

most likely, though, windows has the right driver and its a bad NIC