Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Firefox thinks there's another instance running, but not true

  • 2 replies
  • 0 have this problem
  • 17 views
  • Last reply by pmbrown02

more options

I cannot use, update, uninstall, refresh, or reinstall Firefox (and haven't for four or more years). I always get this message: "Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window." But I have (obviously) shut down the computer entirely any number of times in all those years. What can I do? I will be taking college classes and Firefox is one of the few browsers that the college supports.

I cannot use, update, uninstall, refresh, or reinstall Firefox (and haven't for four or more years). I always get this message: "Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window." But I have (obviously) shut down the computer entirely any number of times in all those years. What can I do? I will be taking college classes and Firefox is one of the few browsers that the college supports.

All Replies (2)

more options

Chosen Solution

more options

Thank you so much. It was the parent.lock file. I was able to refresh Firefox. Just took a few moments.