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replacing sessionstore.js does not help to restore to desired sessions.


I was using FireFox when it was forced to close. When I tried to restore the sessions, when I restarted FireFox, the restore session screen did not show my previous tabs and windows. I proceeded to go online to get help and proceeded to carry out the following:

1. Are you working inside your Profile folder while Firefox is running or not? You shouldn't be. 2. Make sure you have "I have the sessionstore.bak with the info." copy someplace where it won't get overwritten (not In your profile folder at the moment) 3. Open Firefox and set your homepage as Options->General->HomePage When Firefox Starts->Show My Windows and Tabs from Last Time. 4. Close and make sure Firefox is not running at all. 5. Go to your profile folder and delete the sessionstore.js. 6. Copy your sessionstore.bak to that same location (profile folder). 7. Rename the sessionstore.bak to sessionstore.js 8. Close Profile Folder. 9. Open Firefox - you should be presented with the Windows and tabs that are in that sessionstore.

However the previous sessions still did not appear . Tried to force FireFox to close again. Open my profiles folder and now there are 2 sessionstore files. The latest(8KB) and my previous one which contains the sessions that I wanted(86MB).

I deleted this new one and restarted FireFox.

I was only presented with my homepage. I opened another tab (there are now two tabs) and closed FireFox and restarted it again. This time only the latest session with the two new tabs appear.

Apparently FireFox is ignoring my 86MB sized sessionstore.js file.

Can anyone help me on this?

Many thanks in advance, Alvin

Additional System Details

This happened

Not sure how often

This started when...

I tried to replace the sessionstore.js file

Installed Plug-ins

-2007 Microsoft Office System -Active Touch General Plugin Container -Adobe Acrobat -Google Earth Plugin -Google Update -iTunes Application Detector -Java Development Toolkit Java (TM) Platform SE 6 U22 Microsoft Windows Media Player FireFox PlugIn Mozilla Default PlugIn Picasa QuickTime PlugIn 7.6.9 Real JukeBox NS PlugIn RealPlayer Version PlugIn RealPlayer(tm) G2 LiveConnect-Enabled Plug-In(32-bit) RealPlayer(tm) HTML 5 videoShim Plug-In (32(bit) RIM HandHeld Application Loader Shockwave Flash SilverLight Plug-In Windows Presentation Foundation


  • User Agent: Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US) AppleWebKit/534.13 (KHTML, like Gecko) Chrome/9.0.597.107 Safari/534.13

More Information

  • Top 25 Contributor
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624 solutions 8062 answers

Sorry to hear you are having problems, I do not think I can offer help, only some general comments.

Who were you getting help off originally ?
If it was the official firefox help live chat for instance your best course of action may be to go back to them, they will already have the information you provided preveously, and will have the resources to give you accurate replies.

Maybe the file is corrupt, maybe it is even too big for firefox to handle. I wonder if you made the helper aware of the file size ?

I do not have the technical knowledge to know what size files are handled by firefox session restore, but I do know that with my own setup if I had a 1/2 MB sessionrestore file it would probably be unworkable the file sizes on my sytem are often in the 1o s of KB order of magnitude not in MB

Any idea of the approximate number of tabs you may have had open ?

Presumably the data is important and not bookmarked or in your history ? if it is in your history that is probably the fastest method of getting something back. Short of getting someone to try and repair the sesionrestore.js the only other easy alternative I can think of for quicly trying to extract a list of tabs, and so salvage something, would be to work on the file with a word processor.

Make yet another copy of the file or files of interest. Rename it with a .txt ending as a file extension name . You can then quickly go through it manually, or with a word processing macro, and try to extract all the URLs ie look for strings commencing http or https

Question owner

Hey, Thanks John99. Certainly a great alternative.

Will try it out.

Cheers and thanks again! Alvin

  • Top 25 Contributor
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624 solutions 8062 answers

You did not say, have you any idea of how many tabs approximatly would have been open in all windows when the problem occured 10 ? 10o? 1000? >1000+??

I did not know if you had your history turned on or not. If you do try recreating creating by using your History I suggest maybe only open and then bookmark in folders blocks of not more than say 50 tabs, and maybe not going much above 100 tabs open at a time. Also remember to make manual backups of your bookmarks (that includes the history with it) as you work, that way you are not totaly reliant on sessionrestore and autosave bookmarks, and should not be in this predicament again.

  • Top 10 Contributor
  • Moderator
10776 solutions 96959 answers

Make sure that the file extension of the file that you copied is actually .js (right-click: Properties) and not something else. Windows hides some file extensions and that can make you think that the names are the same.

Go to: Control Panel > Folder Options > "View" tab > under "Hidden files and folders", select "Show hidden files and folders"
To see the file extensions of all files uncheck the box "Hide extensions for known file types"

Question owner

Thanks, John99 for the advice.

Thanks Cor-el I have checked and the extension is correct.