Hi, you seem to have tried everything, but since this is site specific, something must be missing! So try deleting ALL references to FB. To do that, open the 3-bar menu, choose History (looks like a clock), then click the Show All History link at the bottom of the list to open the Library window. Search for FB by typing its name in the Search History field in the top-right corner, then press Enter. Now in the search results, right-click on the result, and select Forget About This Site. (Browsing and download history, cookies, cache, active logins, passwords, saved form data, exceptions for cookies, images and pop-ups for that site will be removed). Give it a minute to complete the deletion then try the site (not from an old bookmark) again. More - Delete browsing, search and download history on Firefox

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Hi, Thank you for your response. I did as you requested. Since I had already deleted all history, cache, etc., the only things listed as the Facebook site and all the searches I did in google asking "cannot get into Facebook on Firefox." I deleted the Facebook site (www.facebook.com) reference. I still cannot get in. Grrrrr. In the meantime, I have to try to recreate my old Firefox with the extensions, background, everything that I had for years. I'm getting frustrated here.

Very odd! Can you try another browser on the same PC?

There is a chance that any security programs on your PC may be blocking it, so you could try disabling to test.

You say you've reset (refreshed) FF which would have removed any add-ons - so can't be that, but you could still try Safe Mode, because that temporarily disables a few other things as well - hold down Shift when you start Firefox to start in Safe Mode. More - Diagnose Firefox issues using Troubleshoot Mode, and http://kb.mozillazine.org/Safe_mode

If all else fails, the only other thing I can think of is a clean reinstall, although I don't see why it should work; this means you remove your Firefox program files and then reinstall Firefox. This process does not remove your Firefox profile data (such as bookmarks and passwords), since that information is stored in a different location.

To do a clean reinstall of Firefox, please follow these steps: Note: You might want to print these steps or view them in another browser.

1. Download the latest Desktop version of Firefox from mozilla.org (or choose the download for your operating system and language from this page) and save the setup file to your computer.
2. After the download finishes, close all Firefox windows (or open the Firefox menu and click the close button ).
3. Delete the Firefox installation folder, which is located in one of these locations, by default:
   • Windows:
     • C:\Program Files\Mozilla Firefox
     • C:\Program Files (x86)\Mozilla Firefox
   • Mac: Delete Firefox from the Applications folder.
   • Linux: If you installed Firefox with the distro-based package manager, you should use the same way to uninstall it - see Install Firefox on Linux. If you downloaded and installed the binary package from the Firefox download page, simply remove the folder firefox in your home directory.
4. Now, go ahead and reinstall Firefox:
   1. Double-click the downloaded installation file and go through the steps of the installation wizard.
   2. Once the wizard is finished, choose to directly open Firefox after clicking the Finish button.

More information about reinstalling Firefox can be found here.

WARNING: Do not use a third party uninstaller as part of this process. Doing so could permanently delete your Firefox profile data, including but not limited to, extensions, cache, cookies, bookmarks, personal settings and saved passwords. These cannot be easily recovered unless they have been backed up to an external device! See Back up and restore information in Firefox profiles.

Please report back to say if this helped you!

Thank you.