Wont connect to the Internet

If you can bear with me, I am encountering this problem.

My friend has been trying to set up an internet connection on his uncles computer. Verification of username and password works but the physical connection to the Internet doesnt work. “cannot connect to server”. I know the ISP server is not communicating with the Internet. He tried ping (sent 4 received 0). It also said “request timed out”.

What he then did, was use my account. Connection to server and to the Internet work successfully accessing different websites. He also checked the ping (sent 4 and received 4).

When I tried his account on my computer, I also successfully connected to server and Internet, I also checked Ping (sent 4 and received 4).

Now intially, I thought it was the ISP’s servers that was the problem but now I think its the computer. He also reformatted replacing the modem drivers with new versions and successfully installed Windows2000. But I dont think thats the problem because then how could he had connected to the server?

So would anyone have a clue what might be the problem with the computer connection to the Internet?