Firefox 4 saves the previous session automatically, so there is no longer need for the dialog asking if you want to save the current session.
Use "File > Exit" or "Firefox > Exit" if you want to restore multiple windows.
You can use "Firefox > History > Restore Previous Session" to get the previous session at any time.
There is also a "Restore Previous Session" button on the default about:home Home page.

Another possibility is to use:

• Firefox (Tools) > Options > General > Startup: "When Firefox Starts": "Show my windows and tabs from last time"

Thanks for the response - unfortunately I tried all of the above after reading off the forum - "restore previous session" was not highlighted. On the second piece, I have that set already. I thought their was a way I could go back a week or two and get my settings from then?

Make sure that you not run Firefox in (permanent) Private Browsing - Use Firefox without saving history mode.

• You enter Private Browsing mode if you select: Tools > Options > Privacy > History: Firefox will: "Never Remember History"
• To see all History and Cookie settings, choose: Tools > Options > Privacy, choose the setting Firefox will: Use custom settings for history
• Uncheck: [ ] "Permanent Private Browsing mode"

Thanks. Was good with "remember history" - but double checked to make sure private browsing wasn't checked. Isn't their a file somewhere that I can pick up my a tab settings from some time in the past that I can activate and get my sessions back?

Session data is stored in the file sessionstore.js in the Firefox Profile Folder

• http://kb.mozillazine.org/Profile_folder_-_Firefox
• http://kb.mozillazine.org/sessionstore.js