Session restore unavailable; please help!

User Help for Mozilla Firefox
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Joined: October 6th, 2018, 11:10 pm

Post Posted October 7th, 2018, 10:31 am

I read other questions here about this problem, and tried going to the sessionstore-backups, but it has only 2 files - baklz4 and jsonlz4, and both of them are updated to the most recent time (which is after the previous session I was looking to restore). I tried Jefferson Scher's Scounger tool, but the files show only the tabs that are opened after the Restore Session was gone. I have had Sync turned on, and went to Synced Tabs, but no tabs or anything are there. I had over 200 tabs opened in 3 windows, each. Whenever my laptop went slow, I usually terminated Firefox through Task Manager and then restarted and from there, restored previous session. This time, I was also uninstalling a program from my laptop (while Firefox was closed), and the program opened Firefox to ask why I was uninstalling the program. No page was opened to give the option to restore previous session. I went to History, no option to restore previous session was there. The last time all my tabs were opened was 12 hours ago. I tried restoring Windows to a past point, didn't help. Please help! I will donate a modest sum for successful recovery of my previous session! Thank you very much!

I also used a tool called System Restore Explorer which allows a user to find and copy files in previous Windows Restore Points to find and copy session back-ups to a different drive, and then tried to use the method outlined in topics on official Mozilla forums with the same issue, to restore my session, but to no avail - specifically, this one:

I deleted the session backups in the session-backups folder in the main Profile folder, and replaced the sessionstore.jsonlz4 file with the ones I copied from the previous Windows restore points. There were previous.jsonlz4, recovery.baklz4, recovery.jsonlz4, and upgrade.jsonlz4(with numbers at the end), and I tried to replace the main sessionstore with each one, each time, to no avail. There was no option to restore my session. I tried copying the same files from different Win Restore points, thinking that maybe one restore point was corrupted, but none worked.

Also, when I tried to Jefferson's Scrounger tool to analyze each file, from several Windows restore points, and there were about 10-20 pages decoded, but the rest of the file was filled with the unreadable symbol - square with 4 zeroes partially inside the square. My total session was 3 pages and about 600 tabs opened. Could that be the problem?

On October 2, my Firefox updated to 62.0.3. from 62.0.2. Could this also be the cause? But if that was the cause, then Scrounger should have been able to interpret my session file completely instead of the unreadable symbol.


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Post Posted October 7th, 2018, 1:52 pm

You should have a file from your last update. Is it possible there are other profile folders on your system? They could be either:

* On the Desktop, inside an Old Firefox Data folder
* In the Profiles folder, which is where your currently live and not very useful profile is, does it have any sibling folders if you check one level up?

To avoid the "confirmation page" problem in the future, set Firefox to automatically restore your previous session. It's the first checkbox on the Options page.


The Scrounger looks for certain text in the file and then tries to find URLs that follow it. If there's a huge dump of null characters, then at least one of the URLs is badly corrupted.

Posts: 2
Joined: October 6th, 2018, 11:10 pm

Post Posted October 8th, 2018, 4:59 am

Hi Jefferson Scher!

Firstly, I want to thank you for creating the tool you've provided free of charge for people like me going thru times like these. God bless you!!!

I've looked for other profiles on my laptop, and found none other than the one I'm currently using. I've even tried searching for "old" and "old firefox" on my laptop; first one came with no relevant results, the second came with no results at all.

I can provide you with the session back-up files if needed. If you help me successfully restore my session, I would be more than glad to compensate you for your help, which I really need! Is there anything I can do to try to get my session restored?

Regarding the back-ups, I've tried the back-ups (all 4 versions of them) from different Windows Restore Points, and all of them come up with the null characters.


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Post Posted October 8th, 2018, 9:47 am

Unfortunately, everything I know about decompressing the session history files is already built-in to the tool, so I wouldn't be able to do more with the file than you can do with it.

By default, the Profiles folder is a hidden folder that is invisible to Windows search, so it's really best to explore it yourself. Windows Explorer can expand this "shortcut" path if you paste it into the Windows Explorer address bar and press Enter:


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Joined: September 9th, 2018, 1:41 pm

Post Posted October 8th, 2018, 10:45 am

For next time, just wanted to make sure you know that ctrl-shift-D can bookmark all tabs in a window. Right clicking that folder in bookmarks and "open all in tabs" will then open all those bookmarks. You can make bookmarks backup by copying places.sqlite from your profile, by going to the bookmarks library and clicking import and backup, it has 2 options - backup, and export - both are good to use.

As for your current question, to keep trying to restore old sessionstore backups - I would first, install Firefox Portable. Run it once, close it. Then, try again copying one of those upgrade.jsonlz4* or previous.jsonlz4 files and rename it to sessionstore.jsonlz4 and put it in your Portable folder under data\profile . Then run the portable, if the session doesn't restore automatically click restore previous session in the menus. Press alt to show the history menu if necessary. Also check in the menu recently closed tabs, recently closed windows. If that doesn't work, repeat with one of the other files.

You also may want to use a better file search utility to find jsonlz4 , upgrade, previous, and sessionstore files that you are not yet finding. This one is nice - everything by voidtools.


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Post Posted October 8th, 2018, 1:05 pm

sessionstore-backups, but it has only 2 files - baklz4 and jsonlz4

They may be the file extension names (& offhand I'm not even sure of baklz4), the actual filenames are different.

Whenever my laptop went slow, I usually terminated Firefox through Task Manager

Should only be used as a last resort, IMO.
Greater corruption potential exists otherwise.

There was no option to restore my session

Even manually, through the View (I think it is) menu item?
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