Hi

This support article should help you to remove Firefox:

https://support.mozilla.org/en-US/kb/uninstall-firefox-from-your-computer

I am not sure you read the entire question. I am asking precisely because that instruction works under normal conditions, but not for the situation that I am in.

Can you find the current installation folders for Firefox? When you install from Mozilla's site, that usually would be one of these:

• C:\Program Files\Mozilla Firefox
• C:\Program Files (x86)\Mozilla Firefox

You mentioned the D drive, so perhaps you can find it there somewhere? The previously linked help article references an alternate method for running the uninstaller when when the Windows Registry path to uninstall has become broken. Whether that will clean up the Registry entry(ies), I don't know.

drive:\<some path>\uninstall\helper.exe

If that won't run either, you may need to clean the Windows Installer section of the Registry by hand; that's beyond my knowledge.

Could you try starting Firefox in its Troubleshoot Mode? In that mode, Firefox temporarily deactivates extensions, hardware acceleration, any userChrome.css/userContent.css files, and some other advanced features to help you assess whether these are causing the problem.

Hold down the Shift key when starting Firefox. (On Mac, hold down the option/alt key instead of the Shift key.) A small dialog should appear. Click the Open button.

Note: Don't use the Refresh without first reviewing this article to understand what will be deleted: Refresh Firefox - reset add-ons and settings.

Any less crashy?

The next step would be to submit your crash reports and share crash report IDs here. See: Firefox crashes - asking for support.

Not less crashy. It seems no one here is aware of a last resort un-installation procedure when the normal un-install does not do the job.

Anyway, here is some more details for my specific problematic setup. Two hard drives are involved. Windows 10 installed on C:. Firefox was installed on D:. Then D: became G: after shuffling Sata cables. Windows was able to run Firefox, presumably on G: and also update this version. It worked fine as I rememeber but I probably did not do any extensive internet browsing. Shuffling back Sata cables the original D: is again D: Naturally, I un-installed Firefox from D: when the problem occured. Though Windows settings -> Apps says there are installations remaining on both D: and G: but without being able to remove those.

Installing on C: or D: again and un-install does not fix anything. I just get 'Gah. your tab just crashed' and/or Mozilla crash report after a minute or so. Starting in failsafe mode gave an immediate crash report when Firefox was installed on C: Un-installing and reinstall (was not given the option to choose location with the installer). Then failsafe mode gave me more time before tab crash occured. Not exactly yhe same response but essentially, I cannot use Firefox.

What remains on D: after having un-installed back in time when problems began, are folders Data and plugins. I can manually delete those but it don't seem to change anything.

Refresh Firefox does not change anything. Honestly, all your suggestions are fine for an installation that was always C: or possibly D: or E: ... but there are other situations. I am asking in the forum because the current community articles are useless for my situation.

Ideally it should be possible to install a working instance of Firefox without having to re-install Windows on the PC. But maybe not.