If you have trouble with the upgrade, use this link; http://www.mozilla.org/en-US/firefox/all/

Okay...let's see if I can make this clearer: I UPGRADED and now every single time I attempt to use Mozilla, I am forced to wait while it installs more upgrades. This can involve a wait of up to five minutes just to launch the browser. I DO NOT need to upgrade again.

I see. PLease follow these instructions;

Let’s do a full clean re-install;

Download Firefox For All languages And Systems {web link}

Save the file. Then Close Firefox.

Using your file browser, open the Programs Folder on your computer.

Windows: C:\Program Files C:\Program Files (x86)

Mac: Open the "Applications" folder. https://support.mozilla.org/en-US/kb/how-download-and-install-firefox-mac

Linux: Check your user manual. If you installed Firefox with the distro-based package manager, you should use the same way to uninstall it. See Install Firefox on Linux; https://support.mozilla.org/en-US/kb/install-firefox-linux

If you downloaded and installed the binary package from the Firefox download page, simply remove the folder Firefox in your home directory. http://www.mozilla.org/firefox#desktop ++++++++++++++++++++++++++++ Do Not remove the profiles folder.

Look for, and rename any Mozilla or Firefox program folders by adding .old to them. Do not rename the Mozilla Thunderbird folder if there is one.

After rebooting the computer, run a registry scanner if you have one. Then run the installer. If all goes well, remove the OLD folders when you are done. +++++++++++++++++++++++++++ If there is a problem, start your Computer in safe mode and try again.

http://encyclopedia2.thefreedictionary.com/Linux+Safe+Mode This shows how to Start all Computers in Safe Mode; Free Online Encyclopedia

Thank you for trying, but I've done all of this and still have major issues with FF. It keeps trying to update/upgrade every time I attempt to launch and then it seems to crash within minutes of finally launching. Odd because the other browsers run without issue. I suspect something is conflicting with FF, but don't know what it might be. Just one of those things computers do to drive us nuts! :)

Hi  ! This must be so annoying  ! A complete stab in the dark, but your system details show 'Safe Browsing Version 4 (temporary add-on)' which is part of a Mozilla experiment, called 'Shield Studies'. You'll find that extension in Options => Add-ons => Extensions, where you can either disable or remove it. I don't know if this will make a difference, but it's worth a try - you don't need that extension anyway.

Without even knowing it, you may have 'volunteered' for this Mozilla experiment, called 'Shield studies'

Would you please go to :

Options => Privacy & Security => under 'Data Collection and Use' :

Did you uncheck : 'Allow Firefox to install and run studies' or is it checked  ?

To check if you are enrolled in these studies :

Type in the address bar about:studies

Any extensions that you see listed there, you can either disable or remove.

For further information see : https://support.mozilla.org/en-US/kb/shield

Try to run the Firefox program once as Administrator (right-click: Run as Administrator).