Please explain the problem in detail. What happens? What is/are the exact error message(s) ? [http://www.mozilla.org/en-US/firefox/all/ Download Firefox For All languages And Systems] {web link} [https://www.mozilla.org/en-US/firefox/organizations/ Firefox ESR; Extended Support Release] {web link} Beta, Developer, Nightly versions https://www.mozilla.org/en-US/firefox/channel/desktop/ [https://support.mozilla.org/en-US/kb/install-older-version-of-firefox?cache=no Install Older Version Of Firefox] {web link}