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I am trying to use my Firefox browser, but it doesn't appear on the screen, and the computer says it's already running. Nothing works!

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  • Last reply by FredMcD

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I have been using Firefox for many years and suddenly when I click the shortcut, nothing happens. I tried to uninstall Firefox and then download it again, but I get an error message that says Firefox is running and I must close it before the uninstall will take effect. I can't close it when it won't open. Help

I have been using Firefox for many years and suddenly when I click the shortcut, nothing happens. I tried to uninstall Firefox and then download it again, but I get an error message that says Firefox is running and I must close it before the uninstall will take effect. I can't close it when it won't open. Help

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Reboot your system. Is the problem still there?


How to crash Firefox (All Systems); Instructions here; https://developer.mozilla.org/en-US/docs/Mozilla/How_to_report_a_hung_Firefox

This link has a program that can crash Firefox.

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I've already tried that - still shows Firefox as running, but it doesn't appear on the screen.

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You rebooted, and Firefox is still running? Did you try the Crash Firefox program?

Let’s do a full clean re-install;

Download Firefox For All languages And Systems {web link}

Save the file. Then Close Firefox.

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 ++++++++++++++++++++++++++++ Do Not remove the profiles folder.

Look for, and rename any Mozilla or Firefox program folders by adding .old to them. Do not rename the Mozilla Thunderbird folder if there is one.

After rebooting the computer, run a registry scanner if you have one. Then run the installer. If all goes well, remove the OLD folders when you are done. +++++++++++++++++++++++++++ If there is a problem, start your Computer in safe mode and try again.

http://encyclopedia2.thefreedictionary.com/Linux+Safe+Mode This shows how to Start all Computers in Safe Mode; Free Online Encyclopedia