upgrade from Yosemite to Sierra
I was trying to upgade my mid 2010 iMac from OS X 10.10.5 to 10.12.6 so i can have the newer version of iTunes to work with iOS 13. This line from 'how to get older mac os' http://updates-http.cdn-apple.com/2019/cert/061-39476-20191023-48f365f4-0015-4c41-9f44-39d3d2aca067/InstallOS.dmg seemed to work when I downloaded it from firefox but the when the .pkg file opened saying it was checking to see if it could be installed, it seemed to be running scripts and when installation was complete (which only took a few minutes) I was still on Yosemite.
Tried the same link with Safari but after 5GB download was almost complete it disappeared with no listing in the 'show all downloads' panel. What's going on here? I upgraded a slightly newer iMac from Yosemite to Sierra a few months ago at work with no problem.
Thanks