Could I address the lost tabs part: first, do not exit out of Firefox.

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

• "3-bar" menu button > "?" button > 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 "Show Folder" button

Scroll down to the files whose names start with sessionstore and copy all of them to a safe location such as your Documents folder for potential recovery.

Next, within Firefox, is Restore Previous Session available from either:

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

If it's not grayed out, try that. If it is grayed out, or after that step, are any closed windows or tabs available on those menus for restoration?

For information on older versions of Firefox, please see our support article: Install an older version of Firefox.

Thank you for the info but I had already closed firefox thinking it was simply hung up.

I would like to reinstall the previous version and need information on how to do that. I had followed the link about older versions and saw listed files but do not understand how to find what I need and install it.

You shouldn't use older versions of Firefox as they have serious security issues that could leave your data open to attack. Downgrading will also not bring your tabs back. Did none of Jscher's steps help?

In the profile folder, look for a file with a name similar to

sessionstore.bak-20141006...

and back that up. That is a snapshot of your session at the time of the upgrade. (The newer files may or may not be useful.)

To use that bak file in place of your latest session file, you can try this:

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

• "3-bar" menu button > "?" button > 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 "Show Folder" button

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

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

Pause while Firefox finishes its cleanup, then rename sessionstore.js to something like sessionstore.old. Rename the sessionstore.bak-20141006... file to sessionstore.js (making sure to keep a backup somewhere else just in case).

If Windows does not display the .js extension, please see the following Microsoft support article and turn off extension hiding so you can work as accurately as possible with these files: http://windows.microsoft.com/en-us/windows/show-hide-file-name-extensions

Start Firefox back up again. If it is set to automatically restore your previous session, that should happen. If not, try manually restoring from the History menu.

Any luck?

No, no luck. Clearly I did something wrong because it loaded tabs I used months ago. I know you're trying to be helpful but I am unable to spend so much time with this.

Can you tell please direct me to the correct file/files that will reinstall a previous version of FF - or tell me how to find it myself for future reference? The last update I chose to install was from early September so that would be the version I'm looking for at this point.

Also, if you know, can you please tell me how this updated when my update settings are checked for me to approve updates before they install?

Thank you again for your help.

Try the FTP site.

• https://ftp.mozilla.org/pub/mozilla.org/firefox/releases/

Hi HonorMyChoices, early September would have been Firefox 32.0. There have been 3 small updates to Firefox 32.0, the first two were to fix broken features on some systems and the third to patch a serious security hole.

I'm sure you've seen the dialog that an update is available. Some users have complained that they accidentally triggered that dialog because they were heads down typing or otherwise trying to send input to a page instead of the update dialog. That could be what happened here, but it's just a guess.

I'm careful to avoid that dialog box because more often than not, firefox updates give me grief. Even now, not only are my tabs from earlier lost, but now all tabs close on exit and do not reopen... and I do have my preferences set to show my windows and tabs from the last session.

Try to restore a previous version of the sessionstore.js file.

• Right-click: Properties > Previous Versions

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

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

Hi HonorMyChoices, your original post didn't include a lot of system details, so could you check a couple things:

(1) History settings under:

"3-bar" menu button (or Tools menu) > Options > Privacy

If you have "Firefox will: Never remember history" then every session is private and cannot be restored. You would need to change to "Use custom settings for history" and uncheck the Automatic private browsing checkbox, or switch to "Firefox will: Remember history".

If you have "Firefox will: Use custom settings for history" make sure "Clear history when Firefox closes" is not turned on, or check that the categories that are being cleared do not include Browsing & Download History.

(2) If you do not have the option to re-open a closed tab immediately after you close it:

By default, Firefox should remember up to 10 closed tabs per window. If your Firefox isn't remembering any, your settings may have been changed. Here's how you can check:

• In a new tab, type or paste about:config in the address bar and press Enter. Click the button promising to be careful.

• In the search box above the list, type or paste sess and pause while the list is filtered

• Check these two preferences to see whether they've been zeroed out and either right-click > Reset them to their defaults or double-click and enter your preferred value:
  • browser.sessionstore.max_tabs_undo (default: 10)
  • browser.sessionstore.max_windows_undo (default: 3)