I have Win 8.1.1 Pro 1. If one upgrades Win 8 to Win 8.1 via Windows Store, the Reset and Refresh options are no longer functional. Some one made an extensive report on that.... read this I have to accept it because that was what happened to me when I tried reset or refresh some time ago. That was before the Update 1 install. 2. Because I do system image backup once a week, I never bother to create a bootable USB or DVD. Yesterday I did it just to clear one point. The point is..... if I use bootable Win 8.1 USB or DVD to re-install Win 8.1 in the SAME machine, do I use Win 8 product key ? ( I upgraded Win 8 to 8.1 via Windows Store, so I don't have Win 8.1 key ) Apparently, Win 8 key is ok. My screenshot below shows my Win 8 product key. I assume that is the key I will use for re-installing. I don't need to use a generic key and then change to the real one afterwards.