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My Firefox profile cannot be loaded. Cannot start Firefox or profile manager, have followed other articles

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After a long time, I've decided to reinstall Firefox on my PC. Upon installing it, I got the error "Your firefox profile cannot be loaded. it may be missing or inaccessible." I cannot start Firefox.

After looking online, I found this article on the support page: https://support.mozilla.org/en-US/kb/how-run-firefox-when-profile-missing-inaccessible

I tried opening the profile manager, but can't get to it since Firefox won't start. It also is not accessible through using "firefox.exe -P" in the run dialog box.

So then I followed the directions and found my existing profiles.ini which pointed to my profile file. Wondering if it got corrupted, I changed the file extension to profiles.iniold and moved the whole mozilla folder to my desktop. Firefox continued to give me the same error message.

Finally I uninstalled firefox, deleted the mozilla folder under %appdata%, deleted the Mozilla folder under %programdata%, and deleted any mention of Mozilla in regedit. I finally reinstalled a fresh copy of firefox... and I got the same profile cannot be loaded error.

Is there somewhere that I'm not seeing that needs to be deleted to finally get a fresh install? I don't care about the original profile and am happy to start from scratch, but have no idea what I can still do in order to get to that point. Any suggestions on what I can do to completely remove any remnants of the original install from years ago?

After a long time, I've decided to reinstall Firefox on my PC. Upon installing it, I got the error "Your firefox profile cannot be loaded. it may be missing or inaccessible." I cannot start Firefox. After looking online, I found this article on the support page: https://support.mozilla.org/en-US/kb/how-run-firefox-when-profile-missing-inaccessible I tried opening the profile manager, but can't get to it since Firefox won't start. It also is not accessible through using "firefox.exe -P" in the run dialog box. So then I followed the directions and found my existing profiles.ini which pointed to my profile file. Wondering if it got corrupted, I changed the file extension to profiles.iniold and moved the whole mozilla folder to my desktop. Firefox continued to give me the same error message. Finally I uninstalled firefox, deleted the mozilla folder under %appdata%, deleted the Mozilla folder under %programdata%, and deleted any mention of Mozilla in regedit. I finally reinstalled a fresh copy of firefox... and I got the same profile cannot be loaded error. Is there somewhere that I'm not seeing that needs to be deleted to finally get a fresh install? I don't care about the original profile and am happy to start from scratch, but have no idea what I can still do in order to get to that point. Any suggestions on what I can do to completely remove any remnants of the original install from years ago?

All Replies (2)

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Are you possibly using the Firefox MSIX version from the MS store as that version keeps the profile in a different location ?

You can find the full installer of the current Firefox release (109.0) in all languages and all operating systems here:

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I don't believe I'm using the MSIX version. I downloaded the installer from here: https://www.mozilla.org/en-US/firefox/new/

I did try downloading the full installer of version 109.0, but still have the "Your firefox profile cannot be loaded. it may be missing or inaccessible." error notification.