Network configuration

Unless you have a firewall restricting traffic from this system from the Internet, you need to check your configuration.

Is DNS configured properly? Can you ping a public-published name such as techrepublic.com?

What is configured in the Internet Exlorer browser?

Is the Windows Firewall on?

Have you scanned for malware, viri and trojans?

hello bro....
i think u need to run ur antivirus, because it sometime cause by virus infected.....u need to update ur antivirus b4 u scan....if still cannot access internet, u need to format the pc....cause this problem happen at my office...what i do is....i run antivirus first....if antivirus cannot detect anyvirus..last choice u have is format the pc...

In this order.

Firewall settings.

Corrupted IE.

Cooties in the machine.

Temporary disable the firewall.

Reload IE.

Update or install AV and scan the system.

Run the common cootie removers.

Spybot: Cootie Remover
http://tinyurl.com/ziar

Ad-Aware: Cootie Remover
http://tinyurl.com/tek5

Stinger: Virus Specific Remover
http://vil.nai.com/vil/stinger/
This item will not update through the program. You have to download the new version.

CWshredder: Trojan and Toolbar Cootie Remover
http://tinyurl.com/2bzef

Good Luck Lee

definitely network & or firewall . Assuming not firewall , do your network connection from scratch . delte the old one and add a new one . then redo the small offine network set up giving the name of the workgroup or whatever . then do the internet connection task . give the correct connection method to internet .do it manually . ofcourse don't forget the ip and gateway settings. copy the gateway and dns settings of the copy/similar machine you tested. then from inside ie ( or its properties ) chose and reconfigure the connection tab . erase any unused connection entries in the dial table . go into advanced button in tcp/ip properties and remove any checks in the automatic settings etc.
this will definetly do it. if not check your firewall restrictions . good luck.