Limited Connectivity Problem again

Sorry for bothering all,
I am having the Limited or Low connectivity error of internet connection, too. Please help me.. This is what happend:
I was running a game on my dell desktop when I tried to clean the keyboard, then accidentally (but surely) hit some function keys, so the computer suffered a lot opening realplayer, Outlook.... Of course everything froze. What a mess! I then reboot the system violently( power off and on) Now I got this ' limited or low connectivity' on my Internet connection. I tried disabling and enabling the internet connection, repair to get an IP address, etc. No use. I am crying ..
It is Windows XP home edition. I am using a university LAN connected by cable, not wireless! And the network worked fine before all these happend.
Last week I had just reinstalled the XP and upgraded everthing (including SP2), installed firewall, because of a virus attack. Now I killed my network
Please help me if you have any ideas. Thank you all reading this thread!

 

That's gotta be frustrating.

Simple 'fix' things first. If they don't work, we move on to other things.

- open a command prompt by clicking on start, on run, keying in cmd, and clicking OK. Once there,

Code:

chkdsk /r

and answer as needed to have the disk check run at next boot then reboot.

- when that finishes and windows is restarted, click on start, on run, key in

Code:

sfc /scannow

and click OK. You will probably be asked for your XP install CD.

Post back with results.

 

No dice

I had the same problem as the person above, and after following the instructions above, it simply "verified that all protected Windows files are intact and in their original versions." Then nothing else happened. It didn't ask for a CD or anything. Any suggestions?

Thanks a lot!