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Firefox doesn't work, downloading new version doesn't work, because it says other version is running. But older version is not anywhere for me to uninstall!?!

  • 5 replies
  • 1 has this problem
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  • Last reply by FredMcD

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I've noticed recently blank boxes start appearing on the left side of my screen when starting Firefox. They rapidly open and close. Last night Firefox would not start. I tried downloaded the newest version, which works , but then it always says Firefox is already running and I need to close it before using new version. Yet the only Firefox I can uninstall in the new download. I've done that and tried to download and reinstall again, but always get the message that Firefox is already running. Yet is in nowhere to be found! When I did a troubleshoot, it shows Firefox for Windows 8. My laptop in only a few months old and has always had Windows 10 on it, never Windows 8. Where is the older version of Firefox if it is not visible to uninstall and reinstall?

I've noticed recently blank boxes start appearing on the left side of my screen when starting Firefox. They rapidly open and close. Last night Firefox would not start. I tried downloaded the newest version, which works , but then it always says Firefox is already running and I need to close it before using new version. Yet the only Firefox I can uninstall in the new download. I've done that and tried to download and reinstall again, but always get the message that Firefox is already running. Yet is in nowhere to be found! When I did a troubleshoot, it shows Firefox for Windows 8. My laptop in only a few months old and has always had Windows 10 on it, never Windows 8. Where is the older version of Firefox if it is not visible to uninstall and reinstall?

All Replies (5)

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Let’s do a full clean re-install;

Download Firefox For All languages And Systems {web link}

Save the file. Then Close Firefox. ++++++++++++++++++++ Start your Computer in safe mode.

http://encyclopedia2.thefreedictionary.com/Linux+Safe+Mode This shows how to Start all Computers in Safe Mode; Free Online Encyclopedia +++++++++++++++++++++++++++ Using your file browser, open the Programs Folder on your computer.

Windows: C:\Program Files C:\Program Files (x86)

Mac: Open the "Applications" folder. https://support.mozilla.org/en-US/kb/how-download-and-install-firefox-mac

Linux: Check your user manual. If you installed Firefox with the distro-based package manager, you should use the same way to uninstall it. See Install Firefox on Linux; https://support.mozilla.org/en-US/kb/install-firefox-linux

If you downloaded and installed the binary package from the Firefox download page, simply remove the folder Firefox in your home directory. http://www.mozilla.org/firefox#desktop ++++++++++++++++++++++++++++ Look for, and remove any Mozilla or Firefox program folders. Do not remove the Mozilla Thunderbird folder if there is one.

Do Not remove the profiles folder.

After rebooting the computer, run a registry scanner if you have one. Then run the installer.

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Firefox still will not work because it says a version is running and has to be closed before using the new installed version. Tonight it said it couldn't even continue downloading until Firefox was closed. I've deleted all Firefox files I can find, except one that won't delete. Once again, when I troubleshoot compatibility wise with Windows, it keeps asking what version of Windows I'm using and only allows the choices of XP to Windows 8, even though I have Windows 10.

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Hi, please follow this : *Repair System Registry and Files Find the Dos Prompt or Powershell then Right Click and Run as Administrator then : Copy/Paste to Dos Window : DISM /Online /Cleanup-Image /RestoreHealth then hit Enter. Reboot when completed. Note : DISM goes up to Microsoft for new files if needed.

When comes back up Search for Task Manager and make sure there is no instances of Firefox still there. If there is Click then End Task.

Then try the installer from here : https://www.mozilla.org/firefox/all/

If still issues with it saying Firefox is installed grab this and see if it finds it: https://www.revouninstaller.com/revo_uninstaller_free_download.html

Then use the full version installer.

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Thanks, but I can't understand your instructions.

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