The “Firefox is already running, but is not responding” error has haunted Firefox users for years. You don’t have to restart your computer when you see this error – you can usually fix it with a quick trip to the Task Manager.

This error occurs when Firefox is closed but is still running in the background. Firefox is either in the process of closing or is frozen and hasn’t quit properly. In rare situations, there may be a problem with your profile.

Secure Yourself by Using Two-Step Verification on These 16 Web Services

How to Fix a Stuck Pixel on an LCD Monitor

How to Factory Reset Your Android Phone or Tablet When It Won’t Boot