Uh oh, you closed and re-opened Firefox. When you start up, Firefox saves your previous session tabs from sessionstore.js to sessionstore.bak, but it's only there until you start up Firefox again, when the backup is replaced. So I don't hold out much hope...

But you could take a look here:

Help > Troubleshooting Information > "Show Folder" button

This will open your currently active Firefox settings folder (AKA Profile folder). If you look for sessionstore files, you should see at least sessionstore.js (current session) and sessionstore.bak (previous session). You may also see other files with numbers appended to the name.

Copy all of today's files to a safe location (e.g., Documents folder). The strategy is to work through them to see whether they contain anything useful.

Keeping your profile folder open, switch over and exit Firefox. Then delete sessionstore.js and rename sessionstore.bak to sessionstore.js. After restarting Firefox, can you restore the earlier session (using either History > Restore Previous Session, or the button on the built-in Firefox home page)?

If that isn't the correct one, did you find any other sessionstore files that might be a bit older? If so, repeat the process. If not, unfortunately, it's gone, and you'll have to use your memory or Firefox History (e.g., Ctrl+Shift+h) to reconstruct the missing session.

There is an extension named Session Manager that lets you save more than just the one previous session. If you can't live without your list of tabs, you might want to look into it: https://addons.mozilla.org/firefox/ad.../session-manager/.

Thank you for your quick reply. I had already looked at the session.bak file and it is only 1kb in size so I assume that it doesnt contain the older session. Also there are no other files with numbers appended to them unfortunenately. Looks like I will have to go thru my history and do the best I can, although some tabs havnt been opend in a while so are effectively lost.

 Thanks for the tip on session manager. It is appreciated.

Just a thought.

I do not use Windows much, but there is a recent feature to restore previous files. IIRC that does work on some profile files. So it may be worth a try, attempting to recover sessionstore files, but ensure you backup anything you do have first into a safe, different location.

• see http://windows.microsoft.com/en-US/windows7/Previous-versions-of-files-frequently-asked-questions

Eureka!!!! It worked. Thank you, Thank you. Yes if you click on any file and click on properties it has a tab for previous versions. So I clicked on sessionstore file and it listed 3 previous versions two of which were dated before the crash. I copied all of them directly from the properties previous version tab area (as well as the sessionstore.bak previous versions just to be on the safe side) to a new folder. I then exited firefox per the first suggestion above, and then deleted the sessionstore file, and then copied over the previous version of sessonstore ( that I had copied from the properties window, previous versions tab in a separate folder) from before the crash. I then restarted firefox and it opened with all three windows and all those tabs (way too many. I gotta stop these tabaholic ways). Thank you again for both of your help.

I waited a while before trying the windows previous file idea as too bummed about the crash, and thought it might be too complicated (ie might have to restore whole system). It turned out to be really simple and easy to do.

Glad it is working again. Thanks for posting back.