hello dave, please check in the firefox ''menu ≡ > options > advanced > network > connection - settings...'' that firefox is set up to directly connect to the internet ('no proxy'). [[Firefox can't load websites but other browsers can]] in addition since there is the malicious "general crawler" extension present in your list of addons, please perform a scan of your system with those two free security tools specialised in removing adware and browser hijackers: * [http://www.malwarebytes.org/antimalware/ Malwarebytes Anti-Malware Free] * [http://www.bleepingcomputer.com/download/adwcleaner/ Adwcleaner] [[Troubleshoot Firefox issues caused by malware]]