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Natao arisiva ity resaka mitohy ity. Mametraha fanontaniana azafady raha mila fanampiana.

Suggested solutions do not work for "Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window."

  • 4 valiny
  • 13 manana an'ity olana ity
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  • Valiny farany nomen'i rambosauce

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I keep getting the error "Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window."

I attempted all recommended steps I could find on support (task manager, profile permission settings, etc.) and none of which worked. I even uninstalled Firefox and used other browsers for over a month. Upon reinstallation and launch I keep getting the same error. At this point I've exhausted all the advice I could find on this forum and hope I do not have to abandon Mozilla.

I keep getting the error "Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window." I attempted all recommended steps I could find on support (task manager, profile permission settings, etc.) and none of which worked. I even uninstalled Firefox and used other browsers for over a month. Upon reinstallation and launch I keep getting the same error. At this point I've exhausted all the advice I could find on this forum and hope I do not have to abandon Mozilla.

Vahaolana nofidina

Thank you both for the reply, I understand things are busy.

I am on Windows 7 and had previously tried reinstalling the newest version of Firefox.

I went a little aggressive and deleted the entire Mozilla folder in the AppData directory. Now the newest version has installed and launched with no problem :)

Reinstalling plugins is trivial to go back to using my favorite browser. Cheers!

Hamaky an'ity valiny ity @ sehatra 👍 0

All Replies (4)

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Guess it's goodbye Firefox! It was good while you worked!

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Sorry you never got a reply. Sometimes, we get so many requests for help, that some get lost.

What is your computer system and Firefox?

Have you updated to the current version?

Start Firefox in Safe Mode {web Link} by holding down the <Shift>
(Mac=Options)
key, and then starting Firefox. Is the problem still there?

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Did you try to delete the parent.lock file in the Firefox profile folder?

  • C:\Users\<user>\AppData\Roaming\Mozilla\Firefox\Profiles\<profile>\

"AppData" (XP: Application Data; Mac: ~/Library; Linux: ~/.mozilla) is a hidden folder.


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Vahaolana Nofidina

Thank you both for the reply, I understand things are busy.

I am on Windows 7 and had previously tried reinstalling the newest version of Firefox.

I went a little aggressive and deleted the entire Mozilla folder in the AppData directory. Now the newest version has installed and launched with no problem :)

Reinstalling plugins is trivial to go back to using my favorite browser. Cheers!