The basic steps are to turn off add-ons to see if the problem may be one of the add-ons. * Firefox -> Help -> Restart with add-ons disabled You also want to make sure your plug-gins are up to date: [https://www.mozilla.org/en-US/plugincheck/ Plug-in Check] Lastly, take a look at this article that goes more in depth: [http://support.mozilla.org/en-US/kb/firefox-hangs-or-not-responding|Firefox Firefox Hangs or Not Responding] Hope this helps!