It is possible that a firewall has blocked the new version, see this link for details - https://support.mozilla.com/kb/Cannot+connect+after+upgrading+Firefox

You can also check the connection settings: You can find the connection settings in Tools > Options > Advanced : Network : Connection If you do not need to use a proxy to connect to internet then select "No Proxy" See "Firefox connection settings": *[[Firefox cannot load websites but other programs can]] ---- Other things that need your attention: Your above posted system details show outdated plugin(s) with known security and stability risks that you should update. # Java Plug-in 1.6.0_07 for Netscape Navigator (DLL Helper) # Shockwave Flash 10.0 r32 Update the [[Java]] plugin to the latest version. *http://www.oracle.com/technetwork/java/javase/downloads/index.html (Java Platform: Download JRE) Update the [[Managing the Flash plugin|Flash]] plugin to the latest version. *http://www.adobe.com/software/flash/about/