Well, you can't update. Windows XP is an 18 year old Operating System that isn't supported by Microsoft or Mozilla (or anyone for that matter). it isn't safe to run XP on the internet anymore either, so you should update to either Windows 10 (or buy a new computer) or switch to linux.

Methen said

IAm running xp and have no intennsion of updating I need to get the full copy of this version for back up purposes in case the computer crashes please

If for some reason you can't do as suggested by Tyler Downer, and it's for backup purposes only, you can download from here :

https://ftp.mozilla.org/pub/firefox/releases/52.9.0esr/win32/

Or : you could use the portable Firefox 52.9.0 ESR as it will not interfere with your Firefox release version and Profiles (assuming you will be using a supported Windows version and the latest Firefox version).

https://portableapps.com/apps/internet/firefox-portable-legacy-52

Than you for the link that helped...

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