See: http://kb.mozillazine.org/Error_loading_websites Websites don't load - troubleshoot and fix error messages .......... A possible cause is security software (firewall) that blocks or restricts Firefox without informing you about that, maybe after detecting changes (update) to the Firefox program. Remove all rules for Firefox from the permissions list in the firewall and let your firewall ask again for permission to get full unrestricted access to internet for Firefox. See Configure firewalls so that Firefox can access the Internet and http://kb.mozillazine.org/Firewalls

Thanks cor-el,how and do I look at the firewall? I had a look at windows firewall but I dont realy know what to look for. I have Spyware Doctor with antivirus,do I have to look in there too?(not sure how to though)

Did you look at How to let Firefox use the internet on your Windows computer ?

It ok thanks its fixed. It was the upgrade I did on my spydoctor.Thanks again.

Thalia