• 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: [ ] "Automatically start Firefox in a private browsing session"

• Press F10 or press and hold the Alt key down to bring up the "Menu Bar" temporarily.

Thanks , It Worked

"Recently Closed Tabs" is not enabled. "Recently Closed Windows" is enabled. I want to also enable "Recently Closed Tabs" during a session, but not between sessions. When Privacy is set to, "Use custom settings for history," no check box appears for, "Automatically start Firefox in a private browsing session."

In Firefox 4 that PB mode entry has renamed differently:

[ ] "Permanent Private Browsing mode"

If Recently Closed Windows is active then that means that there is a window closed that has tabs in it. So you can restore such a closed window with all its tabs ot see what comes back. It would be fine if the menu entry would show which tabs there are in such a closed window to make it easier to restore a window with specific tabs.

I use ff4. Whether or not I have opened and closed a window is not relevant to my problem. After I click on the x to close a tab, "Recently Closed Tabs," is never enabled to make it possible to Re-Open that tab, or any other closed tab from the current session. I need to be able to set things so that I may re-open a closed tab in any/every window.