Trying your short solution first. I'm posting now because I think you might actually be onto something here.
I have loaded up the 'Xbox app' (despite never owning an Xbox I might add), which I APPARENTLY HAVE AN ACCOUNT IN! This is huge! It is logged in as my Minecraft username.
So, because I play Minecraft (which I purchased in 2010), I somehow have a 'Microsoft account' (whatever that is), and it does indeed appear that I may be logged in to that with some random username I didn't know about.
I miss the days when you could pay for something and then you could just use it. Crazy to think how agonizing and frustrating the internet/computers have become.
