I used to use Mozilla Firefox regularly. Yesterday it stopped working. I tried to use Internet Explorer to get help from Mozilla. When I did so, all attempts to download Firefox put me into a loop that goes me nowhere. When I click on the Firefox icon nothing happens.
Have you tried Firefox's safe mode? Go to Start > Run and type
If safe mode does not work, try downloading the installer via FTP: ftp://ftp.mozilla.org/pub/firefox/releases/latest/win32/en-US/Firefox%20Setup%2017.0.1.exe