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I have tried to start Firefox but all I get is the error message below

  • 6 replies
  • 64 have this problem
  • 208 views
  • Last reply by cor-el
  • Solved

knackenfur
knackenfur

I have tried to start Firefox but all I get is the message below:

"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".

I have reinstalled Firefox and restarted my PC but I STILL get this message.

I have checked in Windows Task Manager but Firefox is NOT listed as a running process.

Have you any suggestions please?

I have tried to start Firefox but all I get is the message below: "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". I have reinstalled Firefox and restarted my PC but I STILL get this message. I have checked in Windows Task Manager but Firefox is NOT listed as a running process. Have you any suggestions please?

Chosen solution

There are a few possible causes for this, full details are in the "Firefox is already running but is not responding" error - How to fix article.

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All Replies (6)

TonyE
TonyE

Chosen Solution

There are a few possible causes for this, full details are in the "Firefox is already running but is not responding" error - How to fix article.

knackenfur
knackenfur Question owner

Thanks TonyE, after changing my Profile, I am now able to start Firefox again. 8-) However, do you have any ideas how I can retrieve my Bookmarks? (Grrrrrh, I didn't back them up manually, are they auto backed up, do you know?) Cheers Muggins aka Chris 8-(

TonyE
TonyE

You can recover data from the old profile, see Transferring data to a new profile.

knackenfur
knackenfur Question owner

Thanks again TonyE for being patient with me when I should have RTFM! I have followed the procedure and got most of my data back. Thanks again, Cheers Chris 8-)

EricBailey
EricBailey

OK i tried all things,restart, uninstall, taskmanager, new download, Delete folder, Delete all fifefox,checking profile, and even after each one of them and reistalling I still get same message? Firefox also does not like facebook, always crashing durring it.

cor-el
cor-el
  • Moderator
  • Top 10 Contributor

You do still have a Firefox Profile Folder ?

If all Firefox profile folders are removed but there is still a file profiles.ini that links to a non-existing profile then you get the same error message.

See also "Hang at exit":