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Deleted "sessionstore.js" and "sessionstore.-##.js" and am not sure how to get it back?

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I previously asked a question here https://support.mozilla.org/en-US/questions/977547#answer-502020

My problem was that every time I was closing firefox, i would lose all the tabs I had that I needed! it would restore the session before my prior session and not keep the ones i had.

i'm not that tech savy so i tried looking online for a way to resolve it... i chose to follow one of the suggestions to delete all the "sessionstore.js", "sessionstore-##.js" and "sessionstore.bak". I assumed they would refresh new in the folder.

I reset firefox losing all my tabs trying to get them back again. sessionstore.bak came back but i do not have sessionstore.js

i would really appreciate the help thanks!

I previously asked a question here https://support.mozilla.org/en-US/questions/977547#answer-502020 My problem was that every time I was closing firefox, i would lose all the tabs I had that I needed! it would restore the session before my prior session and not keep the ones i had. i'm not that tech savy so i tried looking online for a way to resolve it... i chose to follow one of the suggestions to delete all the "sessionstore.js", "sessionstore-##.js" and "sessionstore.bak". I assumed they would refresh new in the folder. I reset firefox losing all my tabs trying to get them back again. sessionstore.bak came back but i do not have sessionstore.js i would really appreciate the help thanks!

All Replies (4)

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Did deleting the sessionstore files help to fix your problem?

When Firefox starts then Firefox renames the sessionstore.js file from the previous session to sessionstore.bak and creates a new sessionstore.js file for the current session if Session Restore is working properly.

You can try the "Show my windows and tabs from last time" startup setting

  • Tools > Options > General > Startup: "When Firefox Starts"

You can check the browser.sessionstore.* prefs on the about:config page and reset user set (bold) browser.sessionstore.*prefs to the default value via the right-click context menu to make sure that Session Restore is enabled and working properly.


Note that your System Details List shows multiple Flash plugins.

  1. Shockwave Flash 11.9 r900
  2. Shockwave Flash 11.8 r800

You can find the installation path of all plugins on the about:plugins page.

  • (32 bit Windows) C:\Windows\System32\Macromed\Flash\
  • (64 bit Windows) C:\Windows\SysWOW64\Macromed\Flash\

See also "Manually uninstalling a plugin":

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i'm going to get back to this after tonight but i think there is a good chance that this will fix it i hope.

I found out that Tools > Options > General > Startup: "When Firefox Starts" Show tabs from last time

was not set.

So I should expect it to automatically create a sessionstore.js so that I don't lose my information anymmore i guess?

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No, it did not help.

My problem is the exact same.

when I reset firefox I still did not get back the sessionstore.js and "sessionstore-##.js" files i need

Do you have another suggestion? I would really appreciate

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The sessionstore-##.js files are created when Firefox is unable to update sessionstore.js. In other words, they indicate a dysfunction that was present in your pre-Reset profile folder, probably sessionstore.js was locked in some manner.

If you have those deleted files still in your Recycle Bin or in the Old Firefox Data folder created on the desktop when you use the Reset feature, you may be able to scrounge your windows and tabs out of them. These threads have suggestions on how to "mine" the old file to extract the URLs: