Firefox Community Forum

Hello, When I went to launch Firefox after starting up my PC this morning, I was greeted with: "Your Firefox profile cannot be loaded. It may be missing or inaccessible".

I went right to the Mozilla forums and found the help page [https://support.mozilla.org/en-US/kb/how-run-firefox-when-profile-missing...] . In this article it detailed how I should go into my AppData, then Mozilla, then Firefox, and look to see where my profile.ini file is. My profile.ini file was there, alongside the installs.ini and a few other folders. I attempted also to launch the profile manager using run and the "firefox.exe -P" command, but I got the same profile error as when I tried launching the app. The help page then recommended deleting the profile.ini file and then launching Firefox to hopefully remake the default profiles.ini file and enable me to launch Firefox, so I attempted that. When I tried relaunching Firefox, the profiles.ini file did not re-appear in my Firefox folder.

I then tried deleting the Firefox folder itself, and relaunching Firefox. This resulted in it being remade, but with just 2 folders left: Crash Reports and Pending Pings. Obviously that's not ideal, so I right clicked the Firefox folder and used the Windows "Previous versions" feature to restore the Firefox folder to a backup of how it was this morning. I then re-tried launching and I still got the same missing profiles error message. I also briefly attempted manually making a new profiles.ini file with notepad, and pointing it towards my Profile withing my Profiles folder, but that still resulted in the same missing profiles error.

This is basically where I am at now. I have confirmed that I do in fact see my actual profile in my "C:\Users\****\AppData\Roaming\Mozilla\Firefox\Profiles" folder, and as far as I can tell my profiles.ini file correctly points towards it. I did another reset of my Firefox folder to a backup of where I was at this morning before attempting anything. I can confirm my Windows account (Admin, and only account on the computer) has full read and write access to all Folders and files within the Mozilla folder, although I will mention some of the files in the Firefox folder were marked with the "Read-Only" attribute (not sure if that matters, but I tried unchecking those and still no luck)

As far as I can tell I have thoroughly exhausted all the easily accessible tips on the internet for solving this, so I am wondering what to try next?

TLDR: Error: Your Firefox profile cannot be loaded. It may be missing or inaccessible" Already Attempted (And failed): -deleting and prompting a remake of the profiles.ini folder -using firefox.exe -P to launch Profile manager -deleting Firefox folder to prompt a remake of that -multiple uninstalls and reinstalls of Firefox -manually remaking profiles.ini file after it didn't come back after deletion

Will link images of (1) profiles.ini file. (2) Profiles folder.

I had a problem where FF 140.0 would not update, and in trying to get FF yo update, I used a re-install tool to which I was pointed in my problem report. This caused FF to wipe out my configuration, and I lost all my windows and tabs. I have gone to

    \Appdata\Roaming\Mozilla\Firefox\Proifiles\abnfpged.default

cleared all of the data therein, and restored that directory from a backup I made last Monday. But I cannot get FF to use that directory. "about:profiles" shows only two profiles, but the Profiles directory has five profiles:

03/10/2026 09:39 AM <DIR> qf00ka5x.default 03/10/2026 09:39 AM <DIR> v842ceue.default-release 04/11/2026 09:16 PM <DIR> .. 04/11/2026 09:16 PM <DIR> . 04/12/2026 03:08 PM <DIR> abnfpged.default 04/12/2026 06:29 PM <DIR> jdfj91sd.default-release-1775960183850 04/12/2026 06:48 PM <DIR> f1jq4mlq.default

Only the profiles beginning with "j" and "f1" are seen in the "about:profiles" screenshot I have attached. And I have attached a screenshot of my profiles.ini file. Also, in the abnfpged.default directory I restored, where is the list of all of my open windows and tabs? FF used to keep that in a sessionstore.jsonlz4 file, but that file is only written when FF closes. I tried to save a copy when I was having problems, but I stored the copy in the same directory, which FF changed during the re-install process. Here is my profiles,.ini file:

[Install308046B0AF4A39CB] Default=Profiles/jdfj91sd.default-release-1775960183850 Locked=1

[Profile1] Name=default IsRelative=1 Path=Profiles/f1jq4mlq.default

[Profile0] Name=default-release IsRelative=1 Path=Profiles/jdfj91sd.default-release-1775960183850

[Install641D10338ABA448D] Default=Profiles/abnfpged.default Default=1 IsRelative=1 Locked=1

[General]

StartWithLastProfile=1

Version=2

[BackgroundTasksProfiles] MozillaBackgroundTask-308046B0AF4A39CB-defaultagent=lnvi5jn5.MozillaBackgroundTask-308046B0AF4A39CB-defaultagent

I have not worked with the ;profiles.ini file in many years, as my FF configuration has not had problems. Thanks.

Hello I got a pop up or it was new tab informing about new firefox functions. It was about profile creation and management. Now i have two profiles and cant switch back to my old one. I cant seem to be able to delete new profile to return to my old one.

I did the profile thing and there's only one blank profile showing.

I did the CMD prompt -P and there is only Default showing.

This new upgrade has destroyed everything

Before the new profiles update in Firefox I was using the old version of creating profiles and I want to move that profile into the new profile method. Is that possible?

I have an account for standard support release versions, I am now using extended support release version 140.7.0 and a popup notification keeps nagging me to make a new profile. How do I do this?

I just set up my Laptop, and now I`m trying to bring my old Profile in, no chance The picture annected is the last, I see, then nothing more. Furthermore: look, please, on the second, no possibility to find my emails and so

Hello,

I am using Firefox in Malaysia. I updated with the latest browser, but I do not see the new profile management (https://blog.mozilla.org/en/firefox/profile-management/).

Is this feature available in certain countries?

Greetings...

I work with multiple computers that each use Firefox as their web browser. In each of the Firefox installation are bookmarks, history, and passwords that have been saved over time.

Q: Is there a manual method available that I could use to merge/combine two or more of these bookmarks/history/password "collections" into a single collection, then install the new combined collection on one or more of the multiple computers?

Please advise. Thank you very much! Take care...

I have moved my profile to a different location on the hard drive to make backups easier. How do I tell firefox where the profile is now located. c:\users\med\my data\PROFILES\mozillA\*.deFAUlt

Unimportant and mildly disruptive issue: I've been using the about:profiles method to maintain separate profiles. I am aware that this is distinct from the new way to manage profiles (about:profilemanager; https://support.mozilla.org/en-US/questions/1543697 ).

I normally use my default profile (let's call it profile A) to open other profiles (of which there are 6 + a Nightly profile).

However, recently I've noticed that if I open another profile (B) from profile A: Refreshing profile A's about:profiles makes it inactive, with the "Another copy of Firefox has made changes to profiles" error. Now, B's about:profiles correctly displays the different profiles, and I can launch more profiles from here. But A is still shown as the default profile. I've tried this with a few other profiles (C, D), but even with those open, B still seems to have the functional about:profiles page.

Is there any way to reset this, i.e. to make A's about:profiles functional even when profile B is launched?

Edit: I think this is because profile B has the new profile manager enabled, and under this, B is the original profile. I tried setting browser.profiles.enabled to false in the about:config settings but this doesn't seem to help. Oh well!

I'm 70 years old and somehow yesterday I pushed a botton that closed out my dashlane password saver and I nned help getting normal settings back please. I can't get into emails etc. Please call me at [edited from community support forum]

I have a folder/subfolder, Old Firefox Data/ukn05f6l.default-release, on my desktop created 11/30/2024.

Any ideas what it is? It is huge...940mb.

Can I delete it?

Thanks

At startup, Firefox starts with an account setup screen. I have been using current setup for 3 years. Tried troubleshoot mode to no avail. Had same problem 3 years ago.

I have used Firefox for years, both out of conviction and to help protect my privacy, even though I often put up with images and forms not displaying on web pages.

Then, three times in two months, after restarting Firefox, I found all my tabs, bookmarks and browser history had disappeared. The only thing I did between restarts was to run Wise Care 365 to clear some space on my laptop, something I had done hundreds of times before.

The first time the loss occurred I found I had a new profile, a feature I neither wanted nor was consulted about. At least I was able to get back to my original profile. The next two times this proved impossible.

Firefox "support" was of no use. Multiple searches produced nothing which helped. After agonising hours, I was able to retrieve my bookmarks and my Firefox browser history through Microsoft Edge. But as a writer and (award-winning) journalist I cannot afford to risk losing my research and links.

So although I disapprove of some Microsoft business practices. I am moving to Edge. If I have missed something that makes sense of this, I would be pleased to hear it. In the meantime, Mozilla needs to improve its product and customer service.

Wishing its customers well,

Francis Shennan

bold text I don't know what subject: Missing Profile?

Firefox says profile is missing. I found default profile under C:\Users\19pro\AppData\Roaming\Mozilla\Firefox\Profiles. How do I restore it to Firefox?

Thank you, Patricia Schmieg

I got a popup when I opened a new window asking if I want to try out a build in VPN and I logged in to my Google account and after that it did a thing I wasn't expecting, it almost reset my browser but I left another Firefox window open and my data was still there and when I open Firefox my data wasn't there only my account which basally meant from guessing when I login to a Google account it created a completely new profile and mistaken it as the main one then hidden my old one to a point where I think it could get deleted if I close my old profile's window also because I checked profiles and there was only one on all the windows.

Oh and I was trying to export my browser data on the old profile but I didn't found a option, and I tried seeing what the sync feature does and I think when I actually added an account Firefox somehow changed it's mind and now thinks this is a different device or whatever because one of the things in the Connected Services says "Elbey (my username) Firefox on elbey" then another said "Firefox 149, Linux" which these two sound like my devices also because I tried out the sync feature on my old profile and needed to login and it actually worked without doing unexpected stuff which is also how I got this information.