Page cannot be displayed after going back to dial up

Here's my problem: I worked on my friend's computer. I installed my LAN card in his PC, and set up his LAN settings, then downloaded all the latest Windows Updates (which he had never done), then took out the card and uninstalled the card's drivers. I also unchecked proxy server, rechecked "always dial up my default connection."

Now he can't access the internet. He can dial in and connect to the internet, but when he opens IE he gets the "page cannot be displayed error."

I know this problem has to be fixable under "Internet Options" then the "Connections" tab. The question is, where?

Setup a new Internet connection?
Dial up network settings?
TCP/IP settings?

Needless to say, he was very disapointed that he wasn't able to get online. What should I tell him about fixing it?

Thank you so much!

Try this from the command prompt.Type "netsh int ip reset reset log.txt".Then type"ipconfig /flushdns".Then restart the computer.This will reset your ip log and flush the dns.

I think the more simple solution would be to do a System Restore (if he's using XP) to a point before you fiddled with his LAN settings.

Will the system restore undo all the patches he downloaded and installed?

Also, before you installed your LAN card, did you uninstall his modem and dialup drivers?? What OS is he running?