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Not able to recover previous session after Firefox update and crash

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Hello, my problem is as follows:

I had a session open when i updated Firefox. It closed the browser however Firefox didn't show me any indication that it was updating so i tried open it again. Right that moment the update window showed up and somehow Firefox crashed. When i opened it again, my previous session was lost and i have no way of retrieving it. There is no option popping up in the menu that says 'Restore Session' and other methods that i have seen online are a bit difficult to understand.

Also the sessions i can recover are all after Firefox kinda crashed/Firefox updated so i don't know how to get my old session back. The session i want to recover is before i updated to Firefox 62.0 on the 10th, September. (Time stamp would be around 5:30pm CEST)

Oh and i have seen this thread (https://support.mozilla.org/en-US/questions/1204253) and i tried doing it, but the session i want back is not there.... does that mean worst case scenario happened and i won't be able to get my session back? ;____;


This may be a dumb question but would reseting my windows version to 9th, September help? I mean it would erase the update i did for Firefox and should (as much as i know <.<) also reset the setting for Firefox to yesterday's ones correct? But would that help since my problem is on the net surface and not a computer problem >.>


ps: i wanted to upload pictures but it somehow doesn't let me, so if you need them, please tell me and i will try to send them.

Hello, my problem is as follows: I had a session open when i updated Firefox. It closed the browser however Firefox didn't show me any indication that it was updating so i tried open it again. Right that moment the update window showed up and somehow Firefox crashed. When i opened it again, my previous session was lost and i have no way of retrieving it. There is no option popping up in the menu that says 'Restore Session' and other methods that i have seen online are a bit difficult to understand. Also the sessions i can recover are all after Firefox kinda crashed/Firefox updated so i don't know how to get my old session back. The session i want to recover is before i updated to Firefox 62.0 on the 10th, September. (Time stamp would be around 5:30pm CEST) Oh and i have seen this thread (https://support.mozilla.org/en-US/questions/1204253) and i tried doing it, but the session i want back is not there.... does that mean worst case scenario happened and i won't be able to get my session back? ;____; This may be a dumb question but would reseting my windows version to 9th, September help? I mean it would erase the update i did for Firefox and should (as much as i know <.<) also reset the setting for Firefox to yesterday's ones correct? But would that help since my problem is on the net surface and not a computer problem >.> ps: i wanted to upload pictures but it somehow doesn't let me, so if you need them, please tell me and i will try to send them.

Modified by JaVe94

Chosen solution

Hi JaVe94, sorry to hear about this problem. I'm not sure what we'll be able to salvage, but let's go through it. Please do NOT use the Windows system restore feature because that could cause worse issues.

After following my backup steps in the other thread, did you find anything in the latest "update" snapshot, or was it of the empty session and nothing useful?

If there's nothing helpful in the latest "update" snapshot or "previous.js" then please try this:

Accessing Shadow Copies on Windows 7

Open your current Firefox settings (AKA Firefox profile) folder using either

  • "3-bar" menu button > "?" Help > 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, on the Profile Folder row, click the "Open Folder" button. This should launch a new window listing various files and folders in Windows Explorer.

Double-click into sessionstore-backups and right-click recovery.js > Properties, then click the Previous Versions tab

Windows should query restore points for older copies of this file, and you can use Copy... to back up the previous one to a safe location such as your Documents folder or Desktop.

(You also could check previous.js and other files.)

Then you can inspect the contents of that file using the Scrounger tool.

Anything promising?

Accessing Shadow Copies on Windows 8, 8.1, and 10

(1) Set Windows to show hidden files and folders:

https://support.microsoft.com/en-us/help/14201/windows-show-hidden-files

(2) Download and run one of these programs:

Within the most recent restore point shown in the program, you can explore along this path to see whether you can find a recent shadow copy of your profile:

\Users\your-user-name\AppData\Roaming\Mozilla\Firefox\Profiles\

(3) Within the seemingly most recently updated profile folder, double-click into bookmarkbackups and Export any recent files you want to check to a convenient location such as your currently live desktop (not the desktop inside the restore point).

Then you can inspect the contents of that file using the Scrounger tool.

Anything promising?

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All Replies (20)

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Chosen Solution

Hi JaVe94, sorry to hear about this problem. I'm not sure what we'll be able to salvage, but let's go through it. Please do NOT use the Windows system restore feature because that could cause worse issues.

After following my backup steps in the other thread, did you find anything in the latest "update" snapshot, or was it of the empty session and nothing useful?

If there's nothing helpful in the latest "update" snapshot or "previous.js" then please try this:

Accessing Shadow Copies on Windows 7

Open your current Firefox settings (AKA Firefox profile) folder using either

  • "3-bar" menu button > "?" Help > 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, on the Profile Folder row, click the "Open Folder" button. This should launch a new window listing various files and folders in Windows Explorer.

Double-click into sessionstore-backups and right-click recovery.js > Properties, then click the Previous Versions tab

Windows should query restore points for older copies of this file, and you can use Copy... to back up the previous one to a safe location such as your Documents folder or Desktop.

(You also could check previous.js and other files.)

Then you can inspect the contents of that file using the Scrounger tool.

Anything promising?

Accessing Shadow Copies on Windows 8, 8.1, and 10

(1) Set Windows to show hidden files and folders:

https://support.microsoft.com/en-us/help/14201/windows-show-hidden-files

(2) Download and run one of these programs:

Within the most recent restore point shown in the program, you can explore along this path to see whether you can find a recent shadow copy of your profile:

\Users\your-user-name\AppData\Roaming\Mozilla\Firefox\Profiles\

(3) Within the seemingly most recently updated profile folder, double-click into bookmarkbackups and Export any recent files you want to check to a convenient location such as your currently live desktop (not the desktop inside the restore point).

Then you can inspect the contents of that file using the Scrounger tool.

Anything promising?

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Hello, sorry for the late reply, time difference ^^" I tried most of the steps you told me and the System Restore Explorer found restore points from which i was able to extract a file from a few days ago. I think this will be the best i can get since everything else has been overwritten with the date and time right after the update.

Thank you a lot for your help, it was really appreciated ^___^

JaVe94

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jscher2000 said

Hi JaVe94, sorry to hear about this problem. I'm not sure what we'll be able to salvage, but let's go through it. Please do NOT use the Windows system restore feature because that could cause worse issues. After following my backup steps in the other thread, did you find anything in the latest "update" snapshot, or was it of the empty session and nothing useful? If there's nothing helpful in the latest "update" snapshot or "previous.js" then please try this: Accessing Shadow Copies on Windows 7 Open your current Firefox settings (AKA Firefox profile) folder using either
  • "3-bar" menu button > "?" Help > 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, on the Profile Folder row, click the "Open Folder" button. This should launch a new window listing various files and folders in Windows Explorer. Double-click into sessionstore-backups and right-click recovery.js > Properties, then click the Previous Versions tab Windows should query restore points for older copies of this file, and you can use Copy... to back up the previous one to a safe location such as your Documents folder or Desktop. (You also could check previous.js and other files.) Then you can inspect the contents of that file using the Scrounger tool. Anything promising? Accessing Shadow Copies on Windows 8, 8.1, and 10 (1) Set Windows to show hidden files and folders: https://support.microsoft.com/en-us/help/14201/windows-show-hidden-files (2) Download and run one of these programs: Within the most recent restore point shown in the program, you can explore along this path to see whether you can find a recent shadow copy of your profile: \Users\your-user-name\AppData\Roaming\Mozilla\Firefox\Profiles\ (3) Within the seemingly most recently updated profile folder, double-click into bookmarkbackups and Export any recent files you want to check to a convenient location such as your currently live desktop (not the desktop inside the restore point). Then you can inspect the contents of that file using the Scrounger tool. Anything promising?

Hi jscher2000

I got the same problem but your solution was no use for me! Maybe because I closed Firefox and Shut down my PC after losing my previous sessions?

I didn't understand "snapshot" part of your post...

As for "Accessing Shadow Copies on Windows 7" part, I should say "recovery.js" does not exist in my "sessionstore-backups" folder! I only have these file:

upgrade.jsonlz4-20180807170231 upgrade.jsonlz4-20180920131237 upgrade.jsonlz4-20181001155545 previous.jsonlz4 recovery.baklz4 recovery.jsonlz4

Also it should be noted that "Restore Previous Session" button does not exist in History menu!

Is there any hope that I can get my lost sessions back or not?

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Hi esmetozerbezan, in Firefox 56 and later, the extensions changed from js to jsonlz4 when Firefox started compressing the files. If you run Windows 7, try "Previous Versions" for one of those.

If these are hidden or grayed out --

  • "3-bar" menu button > Restore Previous Session
  • (menu bar) History > Restore Previous Session

-- the session might already have been restored. Check either:

  • "Library" toolbar button > History > Recently Closed Windows (and within each restored window, Recently Closed Tabs)
  • (menu bar) History > Recently Closed Windows (and within each restored window, Recently Closed Tabs)

Anything?

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jscher2000 said

Hi esmetozerbezan, in Firefox 56 and later, the extensions changed from js to jsonlz4 when Firefox started compressing the files. If you run Windows 7, try "Previous Versions" for one of those. If these are hidden or grayed out --
  • "3-bar" menu button > Restore Previous Session
  • (menu bar) History > Restore Previous Session
-- the session might already have been restored. Check either:
  • "Library" toolbar button > History > Recently Closed Windows (and within each restored window, Recently Closed Tabs)
  • (menu bar) History > Recently Closed Windows (and within each restored window, Recently Closed Tabs)
Anything?

My version of my Firefox is older at Help > About Firefox:

62.0.3 (64-bit) Firefox is up to date

I get this msg at "Previous Version" tab of any of those 6 files: "There are no previous versions available"

"Restore Previous Session" buttons are hidden as I wrote before.

"Recently Closed Windows" only has one windows with one unimportant tab!

Does it mean that I lost my 20-30 open tabs and can't get them back?!?

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esmetozerbezan said

I get this msg at "Previous Version" tab of any of those 6 files: "There are no previous versions available" "Restore Previous Session" buttons are hidden as I wrote before. "Recently Closed Windows" only has one windows with one unimportant tab! Does it mean that I lost my 20-30 open tabs and can't get them back?!?

Did you already back up the session history files and check the contents of previous.jsonlz4 using my "Scrounger" tool to see what is in there? Or the latest upgrade file? It sounds like that is all you have at this point.

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jscher2000 said

esmetozerbezan said
I get this msg at "Previous Version" tab of any of those 6 files: "There are no previous versions available" "Restore Previous Session" buttons are hidden as I wrote before. "Recently Closed Windows" only has one windows with one unimportant tab! Does it mean that I lost my 20-30 open tabs and can't get them back?!?

Did you already back up the session history files and check the contents of previous.jsonlz4 using my "Scrounger" tool to see what is in there? Or the latest upgrade file? It sounds like that is all you have at this point.

No, I didn't backup anything.

Now I tried all of those 6 files with your "Scrounger" tool and found lost tabs in this one:

upgrade.jsonlz4-20181001155545

Now how can I restore those lost sessions?!

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esmetozerbezan said

I tried all of those 6 files with your "Scrounger" tool and found lost tabs in this one: upgrade.jsonlz4-20181001155545 Now how can I restore those lost sessions?!

If you don't mind losing your current session, you can "swap" the old file in and have Firefox restore it. However, it may be easier just to use the HTML version of the session created by the Scrounger to re-open tabs as needed.

Swap Procedure

To try swapping in an older session history file so Firefox will load it, the standard "manual swap" method is as follows (assuming Firefox is still running):

(1) From inside Firefox, open your current Firefox settings (AKA Firefox profile) folder using either

  • "3-bar" menu button > "?" Help > 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. This should launch a Windows Explorer window listing the various files and folders in your profile.

(2) Leaving that window open, switch back to Firefox and Exit, either:

  • "3-bar" menu button > "power" button Exit
  • (menu bar) File > Exit

Pause while Firefox finishes its cleanup -- a file named sessionstore.jsonlz4 should appear in the folder.

(3) Once Firefox has stopped updating things, while viewing the main level of the profile folder, right-click > Rename sessionstore.jsonlz4 to sessionstoreOLD.jsonlz4

If you see an older sessionstore.js or sessionstore.bak file, move it somewhere else or delete it.

(4) Copy in the other file you want to restore, and rename it with the name appropriate for its format:

  • Compressed file such as recovery.jsonlz4 => sessionstore.jsonlz4
  • Uncompressed file such as recovery.js => sessionstore.js

(5) Start Firefox and it should read the swapped in sessionstore file and restore whatever was in the substitute file; if you do not have Firefox set to restore your previous windows and tabs automatically, use History > Restore Previous Session

Any luck?

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jscher2000 said

esmetozerbezan said
I tried all of those 6 files with your "Scrounger" tool and found lost tabs in this one: upgrade.jsonlz4-20181001155545 Now how can I restore those lost sessions?!

If you don't mind losing your current session, you can "swap" the old file in and have Firefox restore it. However, it may be easier just to use the HTML version of the session created by the Scrounger to re-open tabs as needed.

Swap Procedure

To try swapping in an older session history file so Firefox will load it, the standard "manual swap" method is as follows (assuming Firefox is still running):

(1) From inside Firefox, open your current Firefox settings (AKA Firefox profile) folder using either

  • "3-bar" menu button > "?" Help > 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. This should launch a Windows Explorer window listing the various files and folders in your profile.

(2) Leaving that window open, switch back to Firefox and Exit, either:

  • "3-bar" menu button > "power" button Exit
  • (menu bar) File > Exit

Pause while Firefox finishes its cleanup -- a file named sessionstore.jsonlz4 should appear in the folder.

(3) Once Firefox has stopped updating things, while viewing the main level of the profile folder, right-click > Rename sessionstore.jsonlz4 to sessionstoreOLD.jsonlz4

If you see an older sessionstore.js or sessionstore.bak file, move it somewhere else or delete it.

(4) Copy in the other file you want to restore, and rename it with the name appropriate for its format:

  • Compressed file such as recovery.jsonlz4 => sessionstore.jsonlz4
  • Uncompressed file such as recovery.js => sessionstore.js

(5) Start Firefox and it should read the swapped in sessionstore file and restore whatever was in the substitute file; if you do not have Firefox set to restore your previous windows and tabs automatically, use History > Restore Previous Session

Any luck?

Didn't work!

After closing Firefox no sessionstore.jsonlz4 has been created at profile folder! Anyway after a few minutes I made a copy of that old file and renamed it to sessionstore.jsonlz4 and then launched Firefox, but I saw no positive change!

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esmetozerbezan said

After closing Firefox no sessionstore.jsonlz4 has been created at profile folder! Anyway after a few minutes I made a copy of that old file and renamed it to sessionstore.jsonlz4 and then launched Firefox, but I saw no positive change!

If Firefox didn't create a sessionstore.jsonlz4 file, maybe it didn't shut down fully or is set not to retain history. Hmm...

When you created the copy of the old file and renamed it, did you move it to the main level of the profile folder (i.e., not inside the sessionstore-backups folder)?

Assuming so, Firefox should have read the file at startup (and either restored it automatically if you have that setting, or made it available to restore via the menu).

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jscher2000 said

esmetozerbezan said
After closing Firefox no sessionstore.jsonlz4 has been created at profile folder! Anyway after a few minutes I made a copy of that old file and renamed it to sessionstore.jsonlz4 and then launched Firefox, but I saw no positive change!

If Firefox didn't create a sessionstore.jsonlz4 file, maybe it didn't shut down fully or is set not to retain history. Hmm...

When you created the copy of the old file and renamed it, did you move it to the main level of the profile folder (i.e., not inside the sessionstore-backups folder)?

Assuming so, Firefox should have read the file at startup (and either restored it automatically if you have that setting, or made it available to restore via the menu).

Per Windows Task Manager, Firefox was fully shut down.

I put the renamed file next to those 6 files.

When I launched Firefox it loaded *new previous sessions. One of tabs of *new previous sessions was current page which loaded at launch.

I searched "sessionstore" in main level of the profile folder but found nothing! I suppose that means previous sessions are saved elsewhere under different name...

You wrote "or is set not to retain history." Where is that setting?

Modified by esmetozerbezan

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Hi esmetozerbezan:

(1) The sessionstore.jsonlz4 file is created at the main level of the profile folder, not in the sessionstore-backups folder. When you want to swap it, you need to put it at the main level. Note: This file only exists while Firefox is closed after a normal shutdown. During your live session, Firefox uses recovery.jsonlz4.

(2) History settings are on the Options/Preferences page, Privacy & Security panel. What do you have in the History section? For example:

  • Firefox will: Remember history => good
  • Firefox will: Use custom settings for history => need to verify
    • "Remember browsing and download history" is checked
    • "Clear history when Firefox closes" is NOT checked
  • Firefox will: Never remember history => not good
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jscher2000 said

Hi esmetozerbezan: (1) The sessionstore.jsonlz4 file is created at the main level of the profile folder, not in the sessionstore-backups folder. When you want to swap it, you need to put it at the main level. Note: This file only exists while Firefox is closed after a normal shutdown. During your live session, Firefox uses recovery.jsonlz4. (2) History settings are on the Options/Preferences page, Privacy & Security panel. What do you have in the History section? For example:
  • Firefox will: Remember history => good
  • Firefox will: Use custom settings for history => need to verify
    • "Remember browsing and download history" is checked
    • "Clear history when Firefox closes" is NOT checked
  • Firefox will: Never remember history => not good

(1) The sessionstore.jsonlz4 file does not exist at the main level of the profile folder! My PC has been shut down for some hours but after turning my PC on, that file was not created! Anyway I put the file at the main level of the profile folder but when I launched Firefox I saw no positive change! By "shutdown" what do you mean exactly?!

(2) This option has been chosen > Firefox will: Remember history

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Hi esmetozerbezan, by normal shutdown I mean when you exit Firefox from the menu ("3-bar" menu button > Exit or File > Exit) and Firefox completes its usual shutdown file maintenance.

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jscher2000 said

Hi esmetozerbezan, by normal shutdown I mean when you exit Firefox from the menu ("3-bar" menu button > Exit or File > Exit) and Firefox completes its usual shutdown file maintenance.

So there must be a problem, because FF shutdowns correctly but never creates that file!

Now what should I do to get my previous sessions back?!

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Hi esmetozerbezan, what session has Firefox been restoring instead of the one you wanted? Is it from recovery.jsonlz4, previous.jsonlz4 or another file? Or is Firefox not able to restore any sessions (either automatically or when you use the menu)?

At this point, you might just want to use the HTML page generated by the Scrounger to open the links from the earlier session.

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jscher2000 said

Hi esmetozerbezan, what session has Firefox been restoring instead of the one you wanted? Is it from recovery.jsonlz4, previous.jsonlz4 or another file? Or is Firefox not able to restore any sessions (either automatically or when you use the menu)? At this point, you might just want to use the HTML page generated by the Scrounger to open the links from the earlier session.

Hi jscher2000

Situation is quite confusing.

I opened previous.jsonlz4 , recovery.baklz4 and recovery.jsonlz4 with your tool. Sessions of the fire and the second file are equal so I am not sure Firefox has been restoring sessions from which one!

After that I closed FF then deleted first file and then moved and renamed my own file (which includes correct sessions) in place of the deleted file, after that I launched FF but saw no positive change! Then I deleted the replaced file and then returned the deleted file in its original place and after that I repeated this cycle for the other two files as well but saw no positive result! It should be noted that size of my own file is about two times bigger than any of those 3 files but after closing FF I noticed that my replaced file in place of the first and the third file have been altered by FF because their size has been lowered to approximate size of the original files!!!

So now the only solution is using the HTML page generated by your Scrounger tool?

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Hi esmetozerbezan, I don't have any further ideas.

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Hi jscher2000

Maybe I have to uninstall and then reinstall FF to get things sorted.

Do you know how can I backup my current "bookmarks toolbar" and "active login" information in a way that I can reuse it later?

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esmetozerbezan said

Maybe I have to uninstall and then reinstall FF to get things sorted.

You can if you like. I'm not recommending it. If you think there is a problem with your settings, you can try a Refresh. Please read carefully: Refresh Firefox - reset add-ons and settings.

Do you know how can I backup my current "bookmarks toolbar" and "active login" information in a way that I can reuse it later?

A Refresh should preserve this data, but if you plan to do a full deletion:

Your bookmarks on all 3 "containers" (toolbar, menu, other) can be backed up using these two methods (I recommend using both):

Hopefully you'll only need one of those if you are creating a new profile. These articles describe how to restore/import the files:

I'm not sure what you mean by the term "active logon" but most sites use cookies to recognize that you've logged in, and if the cookies are removed, you'll need to log in again. There is no easy export/import for cookies, but you can preserve the cookies.sqlite file and introduce it to your new profile in place of the new empty one. More generally: Recovering important data from an old profile.

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