Mozila Firefox error: "Firefox is already running but is not responding" on Windows

I use firefox as my default browser, but sometimes when i run it i get this error:

“Firefox is already running but is not responding”

i always need to restart my PC to get that error solved.

is there any other way to avoid that error, or at least solve it without the need to restart my PC all over again every time i get that error.


here is the Screenshot of the error dialog I get:

terminate the old firefox.exe process in the tasks manager.

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Please follow this steps:

  1. Open your tasks manager (either clicking right mouse button on the taskbar or use CTRL+Shift+Escape).

  2. Go to Processes tab.

  3. Look for all processes that are named “firefox.exe” and terminate them by clicking the “End Process” button.

  4. Confirm when you see any confirmation message box.

  5. Now try to run you firefox again (just please make sure you don’t click on firefox twice to run it just once).

You are receiving that error because firefox detected another instance of firefox hanging at background and cannot either close nor start successfully. that usually happens because errors in plugins, slow CPU, or RAM exhausted.

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