Don't exit Firefox! Or if you already did, don't start it back up again! ''If Firefox is running:'' 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. This should launch a new window listed various files and folders. For best results, change the view to "Details". (''If Firefox not running, get to this folder by pasting the following in the Run box on the start menu and pressing Enter:'' %APPDATA%\Mozilla\Firefox\Profiles ''and then double-click into the most recently updated semi-randomly-named folder you find there.'') In the window that launches, scroll down and double-click into the '''sessionstore-backups''' folder. Save all files here to a safe location, such as your Documents folder, so Firefox doesn't overwrite them. We may be able to use them to recover your lost tabs. Also, if you return to the main level of the profile folder, you may find some sessionstore files. Copy those to the safe location as well. Could you report back on what you found? Note: If Windows hides the .js file extension from you, you can change a setting so that you can see all file extensions (this helps when renaming files). This support article has the steps: http://support.microsoft.com/kb/865219 or http://windows.microsoft.com/en-us/windows/show-hide-file-name-extensions ---- The kinds of files you may find among your sessionstore-backup files are: * recovery.js: the windows and tabs in your currently live Firefox session (or, if Firefox is closed, your last session) * recovery.bak: a backup copy of recovery.js * previous.js: the windows and tabs in your last Firefox session * upgrade.js-''build_id'': the windows and tabs in the Firefox session that was live at the time of your last update

Regarding the "shutdownhang" crash, unfortunately these are hard to interpret. Do you recall what Firefox was trying to do at the time?