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Firefox bookmarks & Passwords

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Hello. Last night i had to reinstall windows and i lost everything. but in firefox i have loged in and synced. its also synced with my safari browser on my phone. is it possible in any way to get my bookmarks and passwords back? because everything is gone and the profile folder only shows dates after i installed firefox again!

Best Regards Kaveh

Hello. Last night i had to reinstall windows and i lost everything. but in firefox i have loged in and synced. its also synced with my safari browser on my phone. is it possible in any way to get my bookmarks and passwords back? because everything is gone and the profile folder only shows dates after i installed firefox again! Best Regards Kaveh

All Replies (9)

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Hello Kaveh,

I'm sorry to hear that you lost your bookmarks and passwords after reinstalling Windows. Fortunately, if you have been using Firefox Sync, there is a good chance that you can restore your bookmarks and passwords.

Here's what you can try:

Install Firefox on your newly installed Windows system if you haven't already done so.

Sign in to your Firefox account using the same credentials you used for Firefox Sync.

Once you're signed in, Firefox should start syncing your data, including bookmarks and passwords, from the cloud.

Wait for the sync process to complete. This may take a while depending on the amount of data being synced.

Once the sync is finished, your bookmarks and passwords should be restored in Firefox.

Please note that this process relies on having a recent sync with your Firefox account. If you did not have a recent sync or encountered any issues during the sync process, it might not be possible to recover your data.

I hope this helps you retrieve your bookmarks and passwords. If you have any further questions or need assistance, feel free to ask.

Best regards, Suram Firefox Support Volunteer

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Hi Kaveh, it's not surprising that the files in the profile folder are new, and hopefully your data will repopulate from the Sync cloud. If you want to see what Sync has for your account, here's how you can check on that.

(1) Sign in to your Firefox Account from the main menu button.

Important: do not reset your account password because that will erase all your Sync cloud data.

(2) Install the following add-on from the Mozilla Add-ons site:

https://addons.mozilla.org/firefox/addon/about-sync/

(3) After installation, type or paste about:sync in the address bar to load the add-on's page showing what is in the Sync cloud for your account.

In each category, there should be a "Records (table)" mini-tab to view the data in the cloud.

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On as separate topic, if you had Windows repair or reset itself, it may have saved your old data to a temporary folder. Here's how to check on that.

In Windows File Explorer, look on the C drive for this folder:

C:\Windows.old

If you find that folder:

Set Windows to show hidden files and folders -- this Microsoft article has the steps:

https://support.microsoft.com/en-us/windows/view-hidden-files-and-folders-in-windows-97fbc472-c603-9d90-91d0-1166d1d9f4b5

Then explore that folder up to this point (if it exists):

C:\Windows.old\Users\<username>\AppData\Roaming\Mozilla\Firefox\Profiles\

If you find recent data there, please pause and we can suggest how to use your saved files.

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Hey guys, first i want to thank you for the responses. Sadly i did these things you guys mentioned but it only shows after the install not before even i did sync right before the install. and i did think that since i am logged in i don't have to backup manually.

i have an old backup but its from long ago. don't know how to activate than one as well.

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How old is the backup? If you check for the bookmarkbackups folder, the compressed backup files in there should have their creation dates coded into the file names. Are they recent enough to be worth restoring?

In the same folder where you found the bookmarkbackups folder (i.e., not within that folder), you should find this pair of files:

  • logins.json
  • key4.db

If the backup is really ancient, it might be key3.db rather than key4.db. If you want to extract the logins from those files, you need to keep them together as a pair (like a lock and key).

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Hi again. the backup is from aa year ago but stil better than nothing. the backup files are " JSONI.Z4 " file. havent figured how to restore with that file yet. i think the problem that i could not restore from the sync or the windows.old folder is because i had to install windows twice. Thanks again guys for the responses.

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ari0a said

Hi again. the backup is from aa year ago but stil better than nothing. the backup files are " JSONI.Z4 " file. havent figured how to restore with that file yet.

To check the contents if of a bookmark backup file, you can use my converter (it reads out the backup and generates an HTML Export format file you can open in a tab to review). https://www.jeffersonscher.com/ffu/bookbackreader.html

If the contents are valid, you can use the Restore menu, Choose File open to replace your current bookmarks with the content of the backup file. Or you can Import the generated HTML file to add its contents to your current bookmarks.

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I fixed the bookmarks. could you let me know how to import the passwords as well thank you. I have the Key4 and the Logins.jason and the Logins-backup.jason file.

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I suggest trying this in a test profile first. Here's the drill:

(1) Create and Initialize New Profile

Inside Firefox, type or paste about:profiles in the address bar and press Enter/Return to load it.

Take a quick glance at the page and make a mental note of which Profile has this notation: This is the profile in use and it cannot be deleted. That is your current default profile.

Click the "Create a New Profile" button, then click Next. Assign a name like Test2023, ignore the option to relocate the profile folder, and click the Finish button.

Firefox will switch your default profile to the new one, so click the Set as Default Profile button for your regular one to avoid an unwanted surprise at your next startup.

Scroll down to Test2023 and click its Launch profile in new browser button.

Firefox should open a new window that looks like a brand new, uncustomized installation. (Your existing Firefox window(s) should not be affected.) Please ignore any tabs enticing you to connect to a Sync account or to activate extensions found on your system to get a clean test.

(2) Swap files

On the "Root Directory" row for your Test2023 profile, click the "Open Folder" button.

(A) If you find logins.json (it doesn't usually exist until you save a login), right-click it, click Rename, then add OLD so the name becomes loginsOLD.json.

(B) Right-click the key4.db file, click Rename, then add OLD so the name becomes key4OLD.db.

(C) Paste in your logins.json and key4.db files from your backup.

(3) Restart Firefox in the New Profile and Check Passwords

Back on the about:profiles page, use the "Launch profile in new window" button for Test2023. Then go to the main menu button and check the Passwords page. Did it work?