[Fix] All Bookmarks, Add-ons and Settings Lost, Mozilla Firefox Opens Like a Fresh Installation With New Blank Profile
Table of Contents
PROBLEM SYMPTOMS:
You were using Mozilla Firefox web browser in your computer since few days, months or years without any problem. You customized Firefox Settings (also known as Options or Preferences) and UI according to your requirements. You added your favorite websites and webpages as bookmarks for quick and easy access. You installed several add-ons (extensions, themes, dictionaries, language packs) to add new functionality and features to Firefox.
Everything was working perfectly and suddenly one day when you launched Firefox:
SYMPTOM 1:
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It opened like a fresh installation. In other words, Firefox opened like you performed a clean installation of Firefox in your computer. All your bookmarks, add-ons and custom settings lost/vanished/disappeared. You can’t find your bookmarked websites and installed add-ons in Firefox. Everything was deleted by Firefox.
Now you are forced to use Firefox from scratch and you’ll have to customize all settings, add bookmarks and install add-ons again.
SYMPTOM 2:
Firefox started showing following error message at startup:
You’ve launched an older version of Firefox
Using an older version of Firefox can corrupt bookmarks and browsing history already saved to an existing Firefox profile. To protect your information, create a new profile for this installation of Firefox.
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You get “Exit” and “Create New Profile” buttons on the dialog box.
If you create new profile, you are again forced to use Firefox from scratch.
SYMPTOM 3:
When you launch Firefox, you receive following error message:
Profile Missing
Your Firefox profile cannot be loaded. It may be missing or inaccessible.
When you click on “OK” button, Firefox closes.
PROBLEM REASON:
It’s happening because Firefox upgraded to recently released version 67 or later which comes with a new feature called “Dedicated Profiles per Firefox Installation Architecture“. This new feature allows users to install different versions of Firefox (such as stable, beta, nightly, developer and ESR) in their computers and use them side-by-side with dedicated or separate profiles for each Firefox version.
In older versions of Firefox, a single user profile was shared by all Firefox versions and users were unable to run different Firefox versions side-by-side simultaneously. Sharing same user profile among all Firefox installations also caused profile corruption and browser crashes issues. That’s the reason behind Firefox showing you “You’ve launched an older version of Firefox” error message at startup. Firefox protects you against running older versions of the browser which can lead to data corruption and stability issues.
That’s why to overcome this issue, now newer versions of Firefox come with this new functionality built-in.
When you upgraded to latest version of Firefox, it detected an existing profile which was also used by another version of Firefox. That’s why it created a fresh new blank user profile and started using it.
So your bookmarks, add-ons and settings are not gone or lost. They are still stored in your browser and computer but since Firefox is using a clean profile, it’s not showing them by default.
PROBLEM SOLUTION:
Don’t worry! You have not lost any browser data. You’ll get all your bookmarks, add-ons and settings back in Firefox. You just need to find your previous user profile and set it as default in Firefox so that Firefox always opens with your old profile whenever you launch it.
STEP 1:
First we need to find our old user profile which was working fine in past and contains our browser data such as bookmarks, add-ons and settings.
Close Firefox and open RUN dialog box by pressing WIN+R keys together.
Now type firefox -p and press Enter key. It’ll open Firefox in profile selection mode. Firefox will show a small dialog box to choose your user profile.
The box may contain 2 or more user profiles listed. For example, our Firefox installation contained following 2 user profiles:
- default
- default-release
“Default-Release” is the culprit. It’s the new user profile created by Firefox automatically and Firefox is using this newly created profile as default.
Now select other profile such as “Default” and click on “Start Firefox” button. It’ll launch Firefox with selected user profile.
If this is the old profile which contains all your previous browsing data, then move to STEP 2.
If this is not your previous user profile, close Firefox and again follow STEP 1 from beginning to launch firefox -p. Now check with other profiles listed one by one until you find your previous user profile.
STEP 2:
Now you know the name of your previous user profile in Firefox which stores all your bookmarks, add-ons and customized settings. Now we just need to set it as default so that Firefox starts using this profile by default.
Open Firefox and type about:profiles in address bar and press Enter key. It’ll open Firefox Profile Manager. You’ll notice all user profiles listed there which you saw on firefox -p dialog box.
Look for your previous user profile and click on “Set as default profile” button present below it.
That’s it. Now Firefox will open with your old profile and you’ll get all your bookmarks, add-ons, settings, history, etc back. Everything will be restored by Firefox and now you can use Firefox without any worries.
PS: The default i.e. currently selected profile will show “This is the profile in use and it cannot be deleted” message below its name.
NOTE: If you get “Another copy of Firefox has made changes to profiles. You must restart Firefox before making more changes” error message on about:profiles page, restart Firefox and the error message will disappear. If it still appears, restart your computer.
Also Check:
[Fix] Mozilla Firefox Automatically Suspends Tabs and Reloads When You Visit
You can also use Sync.
Better idea, don’t use Firefox. It has been getting worse anyway
I don’t have the firefox -p option on the Mac? How to do it on maOS?
Thank you so much for this article. I upgraded Firefox yesterday and had “lost” all my tabs and bookmarks. This got them back. Firefox should be a lot more careful and display instructions for users to follow when this type of drastic and devastating change is expected. THANK YOU!!!!
That took a bit of wrangling but worked perfectly. Thank you so much; I would never have figured that out on my own. One thing that might help others: do indeed click “create new profile” because you can’t get to “STEP 2″ until you have a new profile. Your old one will still exist. To get to the profile box as shown with a mac OS, use this website: developer.mozilla.org/en-US/docs/Mozilla/Firefox/Multiple_profiles and follow the instructions using the ” –profilemanager” line in the terminal window.
Thanks again!
You are awesome.You saved my data and bookmarks.May Allah bless you sir.
Best wishes to you
This doesn’t work for me. When I select the older profile and ask Firefox to open it, I get the same dialog about an “older version of Firefox”, and it creates yet ANOTHER profile.
Doesn’t work for me; same issue as Sean
Same issue as Sean and Paul
Same issue as Sean and Paul and Tau any resolution?
^^ You guys need to create a new profile. It seems the previous profile got corrupted in your Firefox installation, click on Create Profile button in profile manager window and it’ll create a new profile for you.
No, my old profile is not corrupt, Firefox just refuses to use it (same as Sean and Paul and Tau). I guess the screws at Mozilla want me to create an online account — not a solution for 100 end users, many NOT tech savvy. Creating a new profile is not an answer, (Neither is Chrome!)
These steps are not working for me. I tried step 1 when I chose my file it will not lunch and gave me the same error.
Would you help?
This problem is annoying
This solution won’t solve the problem at all if you are actually downgrading your firefox
what worked for me is setting environment variable MOZ_ALLOW_DOWNGRADE=1
on linux, you can do that by typing something like
MOZ_ALLOW_DOWNGRADE=1 firefox -P
in your terminal
on windows you probably have to actually set environment variable inside your system dialogue
but I havent tried it yet on windows
This no longer works
Step 2 mostly still works under Ubuntu and Linux Mint (as of May 2020, Firefox ESR 68). I’ve been using this for the last year. But it did not work earlier today on one particular Ubuntu 18.04 system and the above “Using an older version of Firefox…” message kept coming up. In that case, adding t’s MOZ_ALLOW_DOWNGRADE=1 local variable definition let me recover the previous profile with Step 2. Thanks.
Visited tons of articles and this fix was the only one that worked for me. Been using Firefox a bunch since the update, not sure what caused the problem now.
When will you allow us to have tabs on the bottom again? What could possibly be so hard about this?????
I downgraded my firefox in Windows 10 and encountered this issue. The fix did not work for me until I added the System Environmental Variable as suggested by “t on February 16, 2020 at 3:33 pm” above:
MOZ_ALLOW_DOWNGRADE=1