www.mozilla.org/firefox/all/ However since you are using Vista you will get served Firefox 43.0.1 instead of 47.0.1 due to the signing of the .exe's on Windows since 43.0.2 and newer. Not all Vista users keep their system updated with patches like KB2763674 https://support.mozilla.org/en-US/kb/get-latest-version-firefox-windows-xp-vista You can install 43.0.1 and then update in Firefox to current Release or if you do have a updated Vista OS then you can download Firefox 47.0.1 from https://ftp.mozilla.org/pub/firefox/releases/47.0.1/win32/ as you pick you language and download the larger setup and not the small stub.