For the benefit of others, please report back if this solved your problem. Also for the benefit of people reading this, if you start Tor Browser Bundle and check.torproject.org says there's an update, it's a good idea to check the official blog: https://blog.torproject.org They always make a blog post for a new update, sometimes with relevant information. In this case, they posted this: https://blog.torproject.org/blog/new-tor-browser-bundles-firefox-1703esr "Very important: if you've been using the Tor Browser Bundles with Firefox 10.0.x, you must not attempt to overwrite it with the new bundle. Open these into their own directory and do not copy any profile material from older TBB versions." That's where I got this info.