I'm running Windows 10 I've tried the following fixes: * Uninstall (as fully as I could) and reinstalled Firefox. note: I did get and "The code execution cannot proceed because VCRUNTIME140_1.dll was not found. Reinstalling the program may fix this problem" error; but installed this missing dll file in the C:\Windows\SysWOW64 directory. After installing this dll file, I've uninstalled and reinstalled Firefox I'm still getting the same error message?!? I downloaded the file from www.dll-files.com/ * I disabled Bitdefender per manufacturers instructions and it did not fix it, so it wasn't problematic. * I've tried all of the suggested fixes that were stated in Firefox support, such as clearing the cache, etc. * Bitdefender firewall query: "firefox.exe has been allowed" when I check to see if the is blocking it. I've done all of the above stages so many times, I'm sure the "order they're listed" is not the order that I performed them. I'm using Chrome to try and get this issue resolved. My wife is insistent that I fix Firefox as she doesn't want to use Chrome (EXTREMELY old-fashioned when it comes to change - she's 67 years old; yes I'm 69). Does anyone here have a solution for me? Thanks Side note: This computer is a machine I built several years ago (I've probably built 12 computers) that was in storage. I had to send my Dell Alienware Aurora R8 into Dell to get fixed. Upon starting this computer, I updated windows, Firefox and my Anti-virus (which meant uninstalling it on her old machine and reinstalling it on this machine). Firefox was working flawlessly; then the next day it would not load "any" pages.