Hi Bob, sorry to hear about this problem. I assume you already tried exiting Firefox and starting it up again, or restarting Windows. If not, please try those to release any file locks that could be preventing Firefox from running normally. Can you tell whether you are using a new profile? Signs of using a new profile are: (1) Firefox starts up in a factory-default condition, but you can get some of your data back by connecting it with your Firefox/Mozilla Account (through Sync). (2) Firefox mentioned that it was going to perform a Refresh/Reset/Tune-up and there is an "Old Firefox Data" folder on your desktop with recently modified files inside. This folder would contain your old profile and could be mined for useful data. (3) You can find your recent profile on the about:profiles page -- please refer to the following article for steps to check on that: [[Recover lost or missing Bookmarks]].