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Wannan tattunawa ta zama daɗaɗɗiya. Yi sabuwar tambaya idan ka na bukatar taimako.

Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window.

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When I try to open Firefox, I get this message: "Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window." I then clicked close firefox, but the problem was not solved so I uninstalled and reinstalled firefox, but the same thing happened. At this point, I went to Mozilla support and tried the steps in the article, "Firefox is already running but is not responding error message - How to fix it" but the process firefox.exe was not in the processes tab in windows task manager. While it was in the details tab, when I tried to end the process, I got this message: "The operation could not be completed. Access is denied"

What can I do to fix this issue?

Thank you.

When I try to open Firefox, I get this message: "Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window." I then clicked close firefox, but the problem was not solved so I uninstalled and reinstalled firefox, but the same thing happened. At this point, I went to Mozilla support and tried the steps in the article, "Firefox is already running but is not responding'' error message - How to fix it" but the process firefox.exe was not in the processes tab in windows task manager. While it was in the details tab, when I tried to end the process, I got this message: "The operation could not be completed. Access is denied" What can I do to fix this issue? Thank you.

Mafitar da aka zaɓa

Usually when you shut down and restart Windows, Firefox is not running and can be started normally.

Is Firefox set to start automatically with Windows? Microsoft has a utility to investigate what is set to happen at startup: https://technet.microsoft.com/en-us/sysinternals/bb963902.aspx

It's possible that something is firing off a process in your default browser and that is hanging Firefox. You could try switching your default browser to IE (IE may offer to do this when you start it) before shutting down and restarting Windows to see whether that makes any difference.

Karanta wannan amsa a matsayinta 👍 0

All Replies (12)

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I think its not Firefox issue . For me it's windows issue. By the way , open the task manager from your administrative id and try to kill the process. let me know, what's happen.

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Did you try to reboot the computer?

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

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Sorry, the Windows Task Manager changed in Windows 8 and the article needs to be updated for the changed Task Manager layout.

First, when opening the Task Manager, make sure you are viewing all tabs. If you see a More Details button at the bottom, click that.

Then, to find firefox.exe, click the Details tab, which corresponds to the Processes tab from earlier versions of Windows.

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I've already tried to reboot and when I go to task manager and try to end the process, I get a message saying: access is denied

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jul124 said

I've already tried to reboot and when I go to task manager and try to end the process, I get a message saying: access is denied

I don't know why you would get access denied. Is Firefox starting automatically or in the Administrator account, or are you starting it normally under your user account? This could be a Windows 8 thing (I use Windows 7).

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I was using it normally under my user account

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Sounds as though there might not be any convenient workaround: http://superuser.com/questions/585073/how-to-overcome-access-denied-when-killing-process-in-windows

Do you exit Firefox using the menu? Meaning either:

  • "3-bar" menu button > "power" button - the one in the lower right corner
  • File > Exit - if needed, tap the Alt key to activate the menu bar

That may work around some issues with exiting Firefox by clicking a "red X" button.

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I always exit Firefox by clicking the red x in the top right corner

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Please try using the menu instead. Users who have certain add-ons (for example, the Norton Toolbar extension) or certain settings, are finding that Firefox does not shut down properly when using the "red X" button.

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I'll do that in the future But what can I do for now to get back firefox?

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Zaɓi Mafita

Usually when you shut down and restart Windows, Firefox is not running and can be started normally.

Is Firefox set to start automatically with Windows? Microsoft has a utility to investigate what is set to happen at startup: https://technet.microsoft.com/en-us/sysinternals/bb963902.aspx

It's possible that something is firing off a process in your default browser and that is hanging Firefox. You could try switching your default browser to IE (IE may offer to do this when you start it) before shutting down and restarting Windows to see whether that makes any difference.