

To ensure this, it places special lock files in the profile directory.


If you’ve tried everything above – including rebooting your computer – and you still see this message, it’s possible that your Firefox profile is still “locked.” Firefox is designed to ensure that only one copy of Firefox is using a profile at a single time. The “restart your computer” suggestion is for less-experienced users that may not want to deal with the Task Manager – restarting your computer works because it ends all the processes on your computer, including firefox.exe.
