Hello Buchanie, to be honest i don't known for how long firefox with continue to support win xp, which is unsupported from microsoft a long time ago.

My personal opinion.... i think the big problem will arise in the end of 2016 because from 1/1/2017 Windows no longer trusts OCSP signatures made with SHA-1. Win xp can use only signatures with SHA-1, firefox use now both (that's why support xp) SHA-1 and SHA-2.

Let's see, again this is my personal opinion and nothing more.

see for more info : http://social.technet.microsoft.com/wiki/contents/articles/32288.windows-enforcement-of-authenticode-code-signing-and-timestamping.aspx

I'm already seeking linux solution to my xp :-)

thank you

Windows XP has been EOL with support since April 2014.

While Windows XP SP2 is still the minimum ever since Firefox 13.0, the SP2 users cannot run the Firefox setups since Fx 43.0.2 due to signing. They can however install 43.0.1 and update to current if they do not update WinXP to SP3. This is why those with browser useragents showing NT 5.1 (for WinXP) are being served 43.0.1 and not 44.0 on mozilla.org

WinXP SP3 users can run current versions setups including 32-bit Firefox 44.0 on www.mozilla.org/firefox/all/ though to get Fx 44.0 on WinXP you can go to http://archive.mozilla.org/pub/firefox/releases/44.0/win32/ and pick your language.

The Win64 Firefox Releases (existed since Fx 42.0) however require 64-bit Windows 7, 8 (8.1), and 10.

Thanks guys - sounds like I'm safe for a while - then I'll need to upgrade hardware and software together - annoying when my current software and hardware still does everything I need perfectly adequately.

Is that what they call progress?

Thanks for explaining what is going on.

My XP SP3 is working fine and is currently using Firefox version 45.0.2