Firefox Crashed? The way firefox crashed may affect the restauration process. In order to assist you better, please follow the steps below to provide us crash IDs to help us learn more about your crash.

1. Enter about:crashes in the Firefox address bar and press Enter. A Submitted Crash Reports list will appear, similar to the one shown below.
2. Copy the 5 most recent Report IDs that start with bp- and then go back to your forum question and paste those IDs into the "Post a Reply" box.

Note: If a recent Report ID does not start with bp- click on it to submit the report.

(Please don't take a screenshot of your crashes, just copy and paste the IDs. The below image is just an example of what your Firefox screen should look like.)

Thank you for your help!

More information and further troubleshooting steps can be found in the Troubleshoot Firefox crashes (closing or quitting unexpectedly) article.

You can backup the session files in the sessionstore-backups folder in the Firefox Profile Folder to make sure not to lose possible important session data.

previous.js (cleanBackup: copy of sessionstore.js from previous session that was loaded successfully)
recovery.js (latest version of the sessionstore written during runtime)
recovery.bak (previous version of the sessionstore written during runtime)
upgrade.js-<build_id> (backup created during an upgrade of Firefox)

You can copy a file from the sessionstore-backups folder to the main profile and rename the file to sessionstore.js to replace the current file (make a backup copy of the current sessionstore.js).

You can use this button to go to the currently used Firefox profile folder:

• Help > Troubleshooting Information > Profile Directory: Show Folder (Linux: Open Directory; Mac: Show in Finder)
• http://kb.mozillazine.org/Profile_folder_-_Firefox

Cor-el,

After the crash, I opened Firefox and posted on this forum for help. 

I followed theinstruction and copied previous.js from the sessionstore-backups folder and pasted it to my .default folder and renamed it sessionstore.js. Shut down firefox and relaunched and it restored the tabs that were open from the last session AFTER the crash occurred(I want to restore tabs BEFORE the crash.) Repeated the same process with recovery.js instead yet still the same result. I also noticed both files were dated after the crash occurred. Another thing is each time I reopen Firefox, the sessionstore.js I made disappears.

Did you close Firefox before copying the sessionstore.js file?

You need to have Firefox closed when you copy or replace the sessionstore.js file. You can check the dates of the files that you did backup from the sessionstore-backups folder to see if there is one old enough.

Try to restore a previous version of a file, either a sessionstore.js file or a file in the sessionstore-backups follder.

• Right-click: Properties > Previous Versions

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