Internet not working and everything is pluged in! PLEASE HELP FAST!

My computer is not able to connect to the internet. Well I think that it is connected. I know it is plugged in right. I've had about three people come into check it and they say that it is running great, but they don't know why it keeps saying "Page Cannot Be Displayed" I went to my computer's support page and they said to look for 3rd party internet applications, but i don't know what it those are. Can Someone Help Me Fast. I hate having to ask my roommate if i can borrow her comp.

 

are you running win98 or 2000?

 

i am running on Windows XP Professional!

 

Do you have cable, dsl or dailup? Are you connected to a router?

 

Please take a breath and describe your system and internet connection. Any external modems, routers, switches, etc. Type of computer, Windows version, patch level, etc.

If you're more specific, we can be more specific.