I originally upgraded from Windows XP Pro to Windows 8 Pro then Windows 8.1 Pro using a retail upgrade key for Windows XP Pro to Windows 8 Pro x64.
Will my upgrade from Windows 8.1 Pro to Windows 10 Pro activate noting I bought a Windows 8 upgrade key at reduced cost?
Yes it will activate as your 8.1 is licensed. I upgraded to 10 from 8.1 Pro which I got using the same cheap upgrade key.
Yes, if Windows 8.1 is activated currently, then Windows 10 should activate as well.
There are two important things to note:
First make a backup of your things. Preferably a system image of the C:\ drive. Should things go wrong, you will then easily be able to restore your Windows 8.1 system again.
Second, when you go to Windows 10, you must do an upgrade. Not a clean install, but an upgrade. That can be done by using that little flag icon, which you see in the taskbar or you can use the Media Creation Tool to do the upgrade. Anyway, you have to start the upgrade from inside your current Windows installation.
Thanks for the advice. I've already been experimenting with Windows 10 using an unactivated version in a VirtualBox VM to confirm my legacy software & drivers will work.
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