Some problems occur when your Internet security program was set to trust the previous version of Firefox, but no longer recognizes your updated version as trusted. Now how to fix the problem: To allow Firefox to connect to the Internet again;

• Make sure your Internet security software is up-to-date (i.e. you are running the latest version).
• Remove Firefox from your program's list of trusted or recognized programs. For detailed instructions, see

Configure firewalls so that Firefox can access the Internet. {web link}

Using Windows Firewall, updated a few hours ago, all current. Also uninstalled Malware Bites just in case.

Then found the firewall settings and Firefox was in there twice. Deleted them both, browsed the current program files and added the current Firefox.exe. Still not accessing sites.

Start your Computer in safe mode with network support. Then start Firefox. Try Secure websites. Is the problem still there?

Starting Any Computer In Safe Mode (web link) Free Online Encyclopedia

https://www.bleepingcomputer.com/tutorials/how-to-start-windows-in-safe-mode/

https://www.digitalcitizen.life/4-ways-boot-safe-mode-windows-10/ +++++++++++++++++++++++++++++++++++++++++++++++ If the problem goes away with the computer in Safe Mode, the problem is with one of the other programs on the system.

As a test, disable your protection programs.

Been away from home for a while but finally did a safe mode bootup. Still no access to web pages. For now I guess I'll have to just start using a different browser on that computer. No idea what's wrong but everything else on that box works fine. Perhaps this glitch will fix itself after some time but for now I'm tired of messing with this.

Type about:preferences#advanced<Enter> in the address bar.

Under Advanced, Select Network.

[56+] Type about:preferences#general<enter> in the address bar. Look for Network. +++++++++++++++++++++ Look for Configure How Firefox Connects and press the Settings button. If you are using a proxy, make sure those settings are correct. If there is no proxy, first try No Proxy. If there is a problem, then try System Proxy.

Nothing typed in the Firefox web addy window does anything. Clicking on settings from the Firefox pulldown menu also does nothing.

Let’s do a full clean re-install;

Note: Firefox comes in three or more folders on all computers. They are;

Maintenance: (Programs Folder) <Windows Only> Firefox itself: (Programs Folder) And two folders in the profile of each user on the computer for each Firefox profile for that user.

If you remove the Firefox folder, the user profiles would not be affected.

Download Firefox For All languages And Systems {web link}

Firefox ESR; Extended Support Release {web link}

Beta, Developer, Nightly versions https://www.mozilla.org/en-US/firefox/channel/desktop/

Install Older Version Of Firefox {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) Note: Check Both Folders

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 ++++++++++++++++++++++++++++ Look for, and remove any Mozilla or Firefox program folders. Do not remove the Mozilla Thunderbird folder if there is one.

Do Not remove any profile folders.

After rebooting the computer, run a registry scanner if you have one. Then run the installer. +++++++++++++++++++++++++++ If there is a problem, start your Computer in safe mode and try again.

How to Start all Computers in Safe Mode; {web link} Free Online Encyclopedia

You can check for issues caused by a corrupted or incomplete Visual C++ installation that is missing runtime components (Redistributable Packages) required by Firefox, especially VCRUNTIME140_1.dll.

See "Visual Studio 2015, 2017 and 2019":

• https://support.microsoft.com/en-us/help/2977003/the-latest-supported-visual-c-downloads
• https://aka.ms/vs/16/release/vc_redist.x64.exe
• https://aka.ms/vs/16/release/vc_redist.x86.exe

You may not need the latter (32-bit version) if you use 64-bit Firefox. You may have to reboot the computer.

Tried both the clean reinstall and the visual C++.....did not work.

You can check the connection settings.

• Settings -> General -> Network: Connection -> Settings

If you do not need to use a proxy to connect to internet then try to select "No Proxy" if "Use the system proxy settings" or one of the others do not work properly.

See "Firefox connection settings":

• https://support.mozilla.org/en-US/kb/firefox-cant-load-websites-other-browsers-can

Boot the computer in Windows Safe Mode with network support to see if that has effect.

• https://www.bleepingcomputer.com/tuto.../how-to-start-windows-in-safe-mode/
• https://www.digitalcitizen.life/4-ways-boot-safe-mode-windows-10/

Boy oh boy that was a lot of work but I finally resolved this. Apparently it was that missing DLL file the whole time. After uninstalling and reinstalling several times AND trying both the manual insertion of the DLL file AND downloading the C++ from MS I was still seeing the DLL error message when attempting to install Firefox.

As a final last ditch attempt this morning, I uninstalled Firefox, THEN downloaded the C++ patch, THEN restarted the computer, THEN re-downloaded Firefox without any previous default settings. This time the download did NOT present that DLL error message and the browser is connecting and accessing settings as it should! I'm guessing that the restart after downloading that patch may be what actually inserted the missing DLL...not sure since I've uninstalled/reinstalled/re-started this box so many times it's all a blur. Anyway it looks like I'm back in business.

MANY THANKS to all of you who took the time to assist me with this

You're welcome.

Is that about the file(s) I mentioned in my above reply ?

• https://support.mozilla.org/en-US/questions/1345058#answer-1430763

This is the one that I used:

Microsoft Visual C++ 2015-2019 Redistributable (x64) - 14.29.30040