PC won't connect to internet

My pc will not connect to the internet. Firefox gives me "server not found", ie says "page cannot be displayed. I have a laptop on the same wireless router and it is working fine. The pc gives me the same messages using an aircard directly connected to usb.
I ran the "read me first" stuff and went through all the antivirus/cleanup programs and they found nothing, although combofix will not run.

any help is appreciated.

 

Turn your Firewall/AV off and see if it you can connect then, you could also try Safemode with Networking (f8 at boot).

iain.t :major

 

comp will not boot to safe mode. firewall is off. can ping router, will not ping google, yahoo, etc.

 

Go to Internet Options> Connections > select never dial a connection > then LAN Settings> select Automatically detect settings > apply>save>ok

see if that helps.