Fix Firefox Troubleshooting Information is Already Running but is not responding this article will show you steps you can take to fix the following problem in Firefox: “Firefox is already running but is not responding. To open a new window, you must first close the existing Firefox process, or restart your system”.
Generally when you receive this message, Firefox won’t start up at all. So to get it up and running again try the following.
Close the existing Firefox process
In many cases, shutting the existing Firefox process can solve the problem. To do this, open Windows Task Manager and click on the “Process” tab. Find the process “Firefox.exe” and click on “End Process”.
You can now try starting Firefox. If it still doesn’t work, try a reboot. If that still doesn’t fix it, then move on to step 2.
Delete the lock file
If Firefox is not starting up, but there is also no Firefox process running, you need to check if there is a problem with the lock file. If the lock file does not get deleted when Firefox is closed, it can prevent it from opening again.
The lock file will be located in your profile folder for Firefox. The location will vary depending on XP or Vista/Windows 7. Below is the location you should find it for Windows 7 and Vista.
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