Hi rogerg, it's possible to reinstall just the Firefox program files without removing any data, but unless the program files are damaged, that doesn't have a high likelihood of helping.

Since Firefox isn't saying it cannot connect, and isn't saying the tab crashed, one possibility is that Firefox is loading pages but for some reason the tab contents are not visible.

Could you test in Firefox's Safe Mode? In its Safe Mode, Firefox temporarily deactivates extensions, hardware acceleration, and some other advanced features to help you assess whether these are causing the problem.

If Firefox is not running: Hold down the Shift key when starting Firefox. (On Mac, hold down the option/alt key instead of the Shift key.)

If Firefox is running: You can restart Firefox in Safe Mode using either:

• "3-bar" menu button > "?" Help button > Restart with Add-ons Disabled
• (menu bar) Help menu > Restart with Add-ons Disabled

and OK the restart.

Both scenarios: A small dialog should appear. Click "Start in Safe Mode" (not Refresh).

Any improvement?

Thank you Jscher2000 for your good reply. Unfortunately, doing your steps produces nothing. When I hold down the Shift key then select Open in the Firefox menu, the donut twirls for a second, then...nothing at all happens. When I hold down the Shift key and click on the Firefox icon in my quick-start bar, same thing...nothing at all happens. It's as if Firefox is not even installed on my PC even though I can see Firefox .exe executable in my File Location display.

Any thoughts?

I was confused, I thought Firefox was opening but the tab area was blank. You can't even start Firefox at all?

Could you consider whether this might be a firewall issue, see: Configure firewalls so that Firefox can access the Internet.

Also, it's less likely with recent updates, but please check the 64-bit driver issue discussed in this thread: https://support.mozilla.org/questions/1206330

Thanks for responding, Jscher: No, absolutely nothing happens when I try to launch Firefox. Rather than beat a dead horse, I would like to in-install Firefox and download it all over again. But a straight out re-install would delete all my valuable bookmarks. Is there a way to re-install Firefox while saving bookmarks?

A re-install should not delete your bookmarks. When the Firefox installer detects an existing installation, it performs an upgrade-style install. But of course, it doesn't hurt to make a back-up.

See: Back up and restore information in Firefox profiles

And then:

Clean Reinstall

This takes about 5 minutes. It's not about your settings, it's about making sure the program files are clean (no inconsistent or alien code files). As described below, this process does not disturb your existing settings. It's not essential to uninstall Firefox, but you can if you like, saying No to any request about removing personal data.

It only takes a few minutes.

(A) Download a fresh installer for Firefox to a convenient location:

https://www.mozilla.org/firefox/all/

(B) Exit out of Firefox (if applicable).

If you use Microsoft Office, please change your default browser to Internet Explorer temporarily before the next step.

(C) Using Windows Explorer/My Computer (hold down the Windows key and press E to launch it), right-click > rename the program folder as follows (you might have one or both):

C:\Program Files (x86)\Mozilla Firefox =to=> C:\Program Files (x86)\OldFirefox

C:\Program Files\Mozilla Firefox =to=> C:\Program Files\OldFirefox

(D) Run the installer you downloaded in step (A). It should automatically connect to your existing settings.

Any improvement?

Thank you a lot for all your steps. But... I followed the steps for Clean Reinstall and got the download and started running the Firefox Install Wizard, then a pop-up appeared that said I have to close Firefox before proceeding! But Firefox is not running! That is why this whole thread started...Firefox is dead. Why does the Wizard think that Firefox is running? Would it be cleanest for me to uninstall Firefox? It shows in my list of Programs in the Control Panel. But it is NOT running! Any suggestions?

You could check the Windows Task Manager to shut down any stalled Firefox processes. Ctrl+Shift+Esc will call that up.

Then if you find Firefox on the Processes tab, you can terminate it there, or check on the Details tab for firefox.exe.

Well, whatever I did, it worked. I did the clean install per your steps. All seems to be back to normal.

Jscher, YOU ARE A CHAMP! Thank you.