Do you mean that you cannot access the internet using your internet browsers? What happens when you try? What internet browsers have you tried and what error messages do you see?
Did this ever work, and if so, what has changed since then?
Have you tried System Restore to go back to a time when it did work?
If you have no internet access at all, this may be a malware infection, and if so, find some other computer and follow the advice by Grif in his post here;
http://forums.cnet.com/7726-19411_102-5128854.html?tag=posts;msg5128854
Mark
XP home - HP 1034n 2005 - Cannot connect to any outside server for software updates or installs. Cannot update AVG, Malwarebytes, Rhapsody, etc etc etc. My ISP checked proxy settings in my PC and checked my modem and gave up. HELP?

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