Firefox 7 and Internet Connection Issues
In case you come across any users who might be running v7.x of Firefox on Win x86 or x64, and complain of slow performance, can’t/won’t load pages, etc., while other browsers have no problem, below is an Mozilla article which may help.
“If you have a problem connecting to a website, you may see error messages like Server Not Found. This article describes how to troubleshoot problems that cause this error” —
See also,