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Firefox already running, profile missing or inaccessible, cannot kill in task manager

  • 8 replies
  • 5 have this problem
  • 2 views
  • Last reply by FredMcD

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For reference, this is on windows 8

In the past I've (very rarely) had the "firefox is already running" error and was able to fix it by ending the process in task manager. I updated to firefox 36 the other day. Since then, firefox will run perfectly normally for a while, but after some time (varies from minutes to hours) I can no longer load new pages. The loading wheel just keeps spinning.

Once this has happened, if I quit firefox and try to open it again, it will give me "firefox already running" followed by "profile missing or inaccessible" error messages. If I go to task manager, sometimes no firefox.exe is there, sometimes it is and I cannot close it. In either case I still can't start the program.

I tried reinstalling firefox, which did not fix the issue. I've also tried creating a new profile, again to no avail. AVG picks up no malware. I did a system restore to a week ago, which seemed to work for a while, but the problem has started again. I'm looking for a solution other than installing an old version, if possible.

For reference, this is on windows 8 In the past I've (very rarely) had the "firefox is already running" error and was able to fix it by ending the process in task manager. I updated to firefox 36 the other day. Since then, firefox will run perfectly normally for a while, but after some time (varies from minutes to hours) I can no longer load new pages. The loading wheel just keeps spinning. Once this has happened, if I quit firefox and try to open it again, it will give me "firefox already running" followed by "profile missing or inaccessible" error messages. If I go to task manager, sometimes no firefox.exe is there, sometimes it is and I cannot close it. In either case I still can't start the program. I tried reinstalling firefox, which did not fix the issue. I've also tried creating a new profile, again to no avail. AVG picks up no malware. I did a system restore to a week ago, which seemed to work for a while, but the problem has started again. I'm looking for a solution other than installing an old version, if possible.

Modified by llamapooo

All Replies (8)

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Is there a task running called the plugin-container?

You may need to delete the profiles.ini file in order to resolve the updated profiles: See: https://support.mozilla.org/en-US/kb/how-run-firefox-when-profile-missing...

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Do you have the Firefox icon on your quick launch? Right click on it, and select Open New Window. Sometimes this works. If it opens, close it by Menu > File > Exit.


This is not a cure but will make it easier if Firefox locks up in Windows. https://support.mozilla.org/questions/997866 {web link}


Separate Issue; Your System Details shows;

Installed Plug-ins

Shockwave Flash 16.0 r0 Shockwave Flash 11.8 r800

Having more than one version of a program may cause issues.

Grab the uninstaller from here: Uninstall Flash Player | Windows Uninstall Flash Player | Mac Then reinstall the latest version.

Flash Player Version 16.0.0.305
https://www.adobe.com/products/flashplayer/distribution3.html
Shockwave Director Version 12.1.7.157 http://get.adobe.com/shockwave/

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Boot the computer in Windows Safe Mode with network support (press F8 on the boot screen) as a test.

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@guigs2 There's no plugin-container task running. I've already tried deleting profile.ini

@FredMcD I can't open a new window

@cor-el Please elaborate, what are you suggesting I test for?

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Start your Computer in safe mode with networking. Then start Firefox. Try Safe web sites.

Starting The Computer In Safe Mode;
Free Online Encyclopedia

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Thanks FredMcD and cor-el for the suggestion, but could you please explain further. Is your suggestion that running windows in safe mode would be a fix, or that it would be easier to identify the cause of the problem?

Meanwhile, I'm now using firefox v. 34, which doesn't have the issue, but I'm happy to upgrade again and keep troubleshooting here.

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You can look in this article about how to boot Windows 8 in Safe Mode.

That allows to check if other software on your computer is causing this problem.

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llamapooo said

Is your suggestion that running in safe mode would be a fix . . . .

By running in Safe Mode, only limited system programs are running. If the problem is still there, that tells us something. If the problem is gone, that tells us something else.