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firefox wont start. have tried nearly everything to remove and re-install

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  • Last reply by list-a

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Firefox stopped working today. Every time I launch it, it responds with: "Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window."

I launched Task Manager and killed the active processes, relaunched ff - did not resolve the issue.

I have uninstalled and reinstalled ff multiple times - did not resolve the issue.

I have removed the lock as per here: https://support.mozilla.org/en-US/kb/firefox-already-running-not-responding#:~:text=Right%2Dclick%20on%20an%20empty,it)%20and%20click%20End%20Process.

I have verified the access rights as per here: https://www.minitool.com/news/fix-firefox-is-already-running-but-is-not-responding.html

I have completely removed all the mozilla entries from both Program Files AND in the registry, then reinstalled. did not resolve the issue. registry instructions from here: https://www.reddit.com/r/firefox/comments/s9lguc/how_to_completely_uninstall_firefox/

I have tried to delete existing profiles AND create a new profile but I always get an error: "An unexpected error has prevented your changes from being saved." https://support.mozilla.org/en-US/kb/profile-manager-create-remove-switch-firefox-profiles#w_start-the-profile-manager-when-firefox-is-closed

I'm out of things to try. Hate to abandon Firefox but I'm at the end of my capabilities.

Firefox stopped working today. Every time I launch it, it responds with: "Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window." I launched Task Manager and killed the active processes, relaunched ff - did not resolve the issue. I have uninstalled and reinstalled ff multiple times - did not resolve the issue. I have removed the lock as per here: https://support.mozilla.org/en-US/kb/firefox-already-running-not-responding#:~:text=Right%2Dclick%20on%20an%20empty,it)%20and%20click%20End%20Process. I have verified the access rights as per here: https://www.minitool.com/news/fix-firefox-is-already-running-but-is-not-responding.html I have completely removed all the mozilla entries from both Program Files AND in the registry, then reinstalled. did not resolve the issue. registry instructions from here: https://www.reddit.com/r/firefox/comments/s9lguc/how_to_completely_uninstall_firefox/ I have tried to delete existing profiles AND create a new profile but I always get an error: "An unexpected error has prevented your changes from being saved." https://support.mozilla.org/en-US/kb/profile-manager-create-remove-switch-firefox-profiles#w_start-the-profile-manager-when-firefox-is-closed I'm out of things to try. Hate to abandon Firefox but I'm at the end of my capabilities.

Chosen solution

I finally solved this. As noted clearly above, none of the standard uninstall procedures would completely remove firefox to the degree to overcome the original technical issue. And taking all the documented steps (remove profile, remove all entries via regedit, remove program files, etc) also did not resolve the issue to the degree where a reinstall would work.

What did work is outlined here: https://www.repairwin.com/how-to-completely-uninstall-firefox-remove-user-data/. Downloading geekuninstaller completely removed the previous footprint of firefox so that reinstall then worked fine.

Back to using firefox as primary browser.

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To do a clean reinstall of Firefox, please follow these steps: Note: You might want to print these steps or view them in another browser.

Download the latest Desktop version of Firefox from mozilla_org (or choose the download for your operating system and language from this page) and save the setup file to your computer. After the download finishes, close all Firefox windows (or open the Firefox menu New Fx Menu and click the close button Close 29). Delete the Firefox installation folder, which is located in one of these locations, by default: Windows: C:\Program Files\Mozilla Firefox C:\Program Files (x86)\Mozilla Firefox Mac: Delete Firefox from the Applications folder. Linux: If you installed Firefox with the distro-based package manager, you should use the same way to uninstall it - see Install Firefox on Linux. If you downloaded and installed the binary package from the Firefox download page, simply remove the folder firefox in your home directory. Now, go ahead and reinstall Firefox: Double-click the downloaded installation file and go through the steps of the installation wizard. Once the wizard is finished, choose to directly open Firefox after clicking the Finish button.

Regards, Peter

Modified by petergroft

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This did not resolve the problem. As noted above, I've already taken all of these generally basic steps.

In every case -- even after deleting the program files, removing the registry entries, deleting profiles, etc -- the new installation still recognizes that there was a previous installation and whether I select to use previous settings or not, the end result is the same: Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window.

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Chosen Solution

I finally solved this. As noted clearly above, none of the standard uninstall procedures would completely remove firefox to the degree to overcome the original technical issue. And taking all the documented steps (remove profile, remove all entries via regedit, remove program files, etc) also did not resolve the issue to the degree where a reinstall would work.

What did work is outlined here: https://www.repairwin.com/how-to-completely-uninstall-firefox-remove-user-data/. Downloading geekuninstaller completely removed the previous footprint of firefox so that reinstall then worked fine.

Back to using firefox as primary browser.