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Firefox just deleted years of tabs groups and previously saved browsing sessions. Is this data lost forever?

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This deals with multiple problems, regarding Session Manager, TabGroups, and Firefox Restore.

First, I've been successfully using Session Manager and Tab Groups for a long time. I would open dozens of tabs while conducting research, group the tabs, then save the session.

Then suddenly, today when I went to open a previous tab group (of say 20 tabs), the group would open with zero tabs. This happened to any group I attempted to open.

So, I went to an earlier browsing session that contained many of the same tabs, in the same tab group, only to see that any Tab Group that had been reduced to ZERO (0) in later sessions, had also been reduced to ZERO in every EARLIER instance of that same Tab Group!

So basically, any time I attempted to access a particular group of tabs, those tabs would disappear. I attempted to investigate the Mozilla website to find a solution. All I could find was repeated references to Restoring Firefox to its default settings. I thought, okay, I'll give that a try.

So, I restored Firefox to its defaults, only to find that it removed all extensions and add-ons, and all related data. My browsing sessions for the past four years were gone, as were all my tab groups. This is not what I wanted!

So, I attempted a System Restore only to find it did nothing to restore my Firefox settings or the lost data. I did notice a file pop up on my desktop called "Old Firefox Data", but I don't know what it is or whether it can help me to restore my lost, precious data.

Can anyone help me, please?

This deals with multiple problems, regarding Session Manager, TabGroups, and Firefox Restore. First, I've been successfully using Session Manager and Tab Groups for a long time. I would open dozens of tabs while conducting research, group the tabs, then save the session. Then suddenly, today when I went to open a previous tab group (of say 20 tabs), the group would open with zero tabs. This happened to any group I attempted to open. So, I went to an earlier browsing session that contained many of the same tabs, in the same tab group, only to see that any Tab Group that had been reduced to ZERO (0) in later sessions, had also been reduced to ZERO in every EARLIER instance of that same Tab Group! So basically, any time I attempted to access a particular group of tabs, those tabs would disappear. I attempted to investigate the Mozilla website to find a solution. All I could find was repeated references to Restoring Firefox to its default settings. I thought, okay, I'll give that a try. So, I restored Firefox to its defaults, only to find that it removed all extensions and add-ons, and all related data. My browsing sessions for the past four years were gone, as were all my tab groups. This is not what I wanted! So, I attempted a System Restore only to find it did nothing to restore my Firefox settings or the lost data. I did notice a file pop up on my desktop called "Old Firefox Data", but I don't know what it is or whether it can help me to restore my lost, precious data. Can anyone help me, please?

All Replies (6)

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First, take a deep breath.

The folder on your desktop contains your old settings from before the "Reset." To restore that folder, try this:

(1) Open your Old Settings Folder and keep this window handy.

(2) With Firefox completely closed, start up in the profile manager. You can do that from the Start menu, search box, by typing this and pressing Enter:

firefox.exe -P

(3) Create a new profile, accepting the default location, then start Firefox in the new profile.

(4) Open your newly created settings folder using Help > Troubleshooting Information. This will launch Windows Explorer to that folder. Keep this window open and exit Firefox.

(5) After Firefox exits, pause until file updates are finished, then clear out that new settings folder.

(6) Copy all of the contents of the Old Firefox Settings folder into this newly emptied folder. (I recommend copying rather than moving in case something goes wrong here.)

(7) Restart Firefox and you should be back in your pre-Reset profile.

Did that work so far?

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jscher2000, Thanks for coming to the rescue! I followed your instructions and made it all the way until point #4 "Open your newly created settings folder". I am running Windows Vista (if that matters) and could see no "setings folder"; I did however see a "Profile folder". I tried opening the Profile folder. I was successful at using help to run the Troubleshooting Information, and yes it did open Windows Explorer. But that's where the process ended for me. I exited Firefox, but did not clear out any "new settings folder" because I could not find any folder labeled as such.

What did I miss? Might it have had another label?

Thank you so much for your help; I feel so close to getting my info back again. I just need to figure out these last couple steps.

Thanks again!

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Yes, when you use the Show folder button, you are in the Firefox profile folders area:

C:\Users\username\AppData\Roaming\Mozilla\Firefox\Profiles\gibberish.sometext

It's that gibberish.sometext folder that I meant when I said "Show Folder" opened your personal settings folder. You are there!

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I have recently been getting a message when I open Firefox that it seems to be running slow and I should do a reset. I have done the above procedure regarding creating a new profile and copying everything from my old profile to the new one, but after a month, I'm getting the same message again. Am I doing something wrong?

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Hi victord66, does Firefox seem slow to you? If not, I would ignore it. Firefox may be judging from the startup time, which can be influenced by the number of add-ons you have and other factors. If that time doesn't seem excessive, or you don't want to disable or remove any add-ons, then a Reset isn't the right remedy.