ug from reinstalled Win8 to Win8.1

[1101]

Hi there
With a Win8 re-install , I want to do the free upgrade to 8.1

The official way is via the MS Store, but that requires all the Win8 winupdates to be installed first .
From memory (a year or 2 ago) there were only a few actual updates required, but I dont have that list anymore

So, can I just use a Win8.1 CD/USB & use that to do the ug , over the top of Win8 ?

[1101]

also , the bios emdedded activation/install key has gone missing from the bios
Has anyone seen that happen before . Its just gone, the apps I use to extract bios embedded keys find nothing .

Luckliy I have that key in a txt file , from when I extracted it a year back. Otherwise I wouldnt be able to activate .
I bit disturbing that it can disappear, or no longer be detected in the bios

[zqwerty]

"the bios emdedded activation/install key has gone missing from the bios"

Think that only started with Win10%, before that I thought one always had to re-enter the activation/installation key on any reinstall.

I stand to be corrected on this.