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After Firefox asked to update, I clicked NO! it did it anyway and now I've lost my previous session. How do I get it and my saved passwords etc. back?

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When firefox asked if I wanted to update to the newest version, I answered NO! I had already discovered on my other computer that if I allowed the update, I would lose my ability to restore the previous session, so I wanted to save the tabs so I could reload them. I also lost all of the saved passwords on my other computer and didn't want the same thing to happen on my work computer. But despite answering NO. Firefox updated anyway, and I have lost days of work. How do I get it back? Jack

When firefox asked if I wanted to update to the newest version, I answered NO! I had already discovered on my other computer that if I allowed the update, I would lose my ability to restore the previous session, so I wanted to save the tabs so I could reload them. I also lost all of the saved passwords on my other computer and didn't want the same thing to happen on my work computer. But despite answering NO. Firefox updated anyway, and I have lost days of work. How do I get it back? Jack

All Replies (4)

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In the event that the passwords information is lost, you should record all information in a separate text file somewhere else on your hard drive, or written down. You can easily copy and paste if you need to do so. If you are concerned about someone else looking at that file, you can compress it using a password.


Look on your desktop. Do you see a folder called; Old Firefox?

https://support.mozilla.org/en-US/kb/recovering-important-data-from-an-old-profile

https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles

https://support.mozilla.org/en-US/kb/how-run-firefox-when-profile-missing-inaccessible


Type about:profiles<enter> in the address bar. How many profiles are listed? How many should be there?

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I do have all of my passwords saved to a file. So I can reenter them one at a time. But it is a lot of additional steps. I have one profile listed and it is the default profile. There is not a file labeled old Firefox on the desktop. Any other suggestions?

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The only thing I could suggest is that you Copy your Firefox profile folder to a safe location, and make new copys each day.

This way if something goes wrong, you can Copy the 'clean' file back to the profile, overwriting the corrupt files.

There's an add-on that can do this, but it's not compatible with v57.

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Hi Jack, you posted from Waterfox but the problem is with Firefox? What version of Firefox?

Firefox 56 uses a different session history file format from Firefox 55 and presumably Waterfox 55. In Firefox 56, the files are compressed and the extension changes:

recovery.js => recovery.jsonlz4

and so forth.

Please back up everything in the sessionstore-backups folder for potential recovery. To get to that folder:

First: Do not exit Firefox, or if you closed it, don't re-open it.

(1) To open your profile folder...

If Firefox is still running:

You can open your current Firefox settings (AKA Firefox profile) folder using either

  • "3-bar" menu button > "?" button > Troubleshooting Information
  • (menu bar) Help > Troubleshooting Information
  • type or paste about:support in the address bar and press Enter

In the first table on the page, click the "Open Folder" button.

If Firefox is closed:

Type or paste the following into the Windows Run dialog or the system search box and press Enter to launch Windows Explorer:

%APPDATA%\Mozilla\Firefox\Profiles

In that folder, do you see a semi-randomly-named folder? If so, click into it. If you find multiple such folders, find the one that was most recently updated.

(2) Copy out session history files

In your profile folder, scroll down and double-click into the sessionstore-backups folder. Save all files here to a safe location, such as your Documents folder. If not too much time has passed, we may be able to use them to recover your lost tabs.

(3) What files did you find?

The kinds of files you may find among your sessionstore files are:

  • recovery.js/jsonlz4: the windows and tabs in your currently live Firefox session (or, if Firefox crashed at the last shutdown and is still closed, your last session)
  • recovery.bak/baklz4: a backup copy of recovery.js
  • previous.js/jsonlz4: the windows and tabs in your last Firefox session
  • upgrade.js/jsonlz4-build_id: the windows and tabs in the Firefox session that was live at the time of your last update

To examine the contents of one of these files, you can drop it onto a tool on my website:

https://www.jeffersonscher.com/res/scrounger.html