I had this problem as well, but was able to solve it using this procedure: - Close firefox from the menu (don't use the 'x' as firefox may continue to run in memory for a while) - in your start menu, enter the following into the "run" prompt: firefox.exe -P - The firefox profile manager will open (see attached image) - In my case I deleted the "default" profile because I didn't care about losing any settings. You may want to simply create a new profile instead in case you need to save your settings. - To avoid being asked about which profile to be used you can highlight your new profile and then make sure the "Don't ask at startup" checkbox. When ready, press the "Start Firefox" button. - Voila! That fixed it for me. Like I said, I just created a new "default" profile and everyone worked fine for me; use your own judgement here. Good luck!