Hi Gary, have you tried using the "full" or "offline" installer? That is available from the following page (more info: Custom installation of Firefox on Windows):

https://www.mozilla.org/firefox/all/#product-desktop-release

That works around issues with the small/stub installer needing permission to download more files.

After installation, if problems continue:

You might try starting Firefox in its "Safe Mode" by holding down the Shift key when launching the Firefox desktop shortcut. (Choose Safe Mode from the small panel, not Refresh.)

Thank you for trying to help. I tried what you recommended. It appeared to install yet it will not open any website - it is like it isn't connected to the web. Perhaps I don't know what I'm doing but I have used Firefox for years and had no trouble until now.

Did starting in Firefox's Safe Mode make any difference?

Another user reported that no pages would load after updating their internet service. You might peruse this thread to see whether any of the discussion is helpful: https://support.mozilla.org/questions/1299409 (unsolved)

Nothing seems to be working. Now I'm gettings the attached message.

It acts like it loads the whole program but it doesn't. It gives you an icon and you can open a black browser page but it won't do anything.

Then the firefox disappears like it closes. It doesn't it leaves a file dangling I have to delete thru task manager. It's all turning into a viscous circle.

Hi Gary, that message about the missing DLL has come up in some other threads. I'm not sure what the best solution is, but could you take a look:

https://support.mozilla.org/en-US/search/advanced?sortby=1&a=1&w=2&q=%22vcruntime140_1.dll%22