Hi, so I bought a prebuilt pc with windows 8.1 oem version. In 2015, I was offer'd a free windows 10 upgrade and I accepted. Can't remember how that process went, anyway a few years ago I upgraded my MB and had to enter my 8.1 product key that is posted on a lil sticker on the side of my pc tower and it worked. I want to get an ssd and put windows 10 and use my product key, (question) will it be accepted again? Thx in advance.