Just setup 7 ultimate on a laptop then updated to 10 Pro, then removed the ssd, put into my desktop and wiped the main partition and the partition with the BCD so I could do a fresh install, but there was a 500mb recovery partition remaining at the end of the drive.

Then I setup Win 10 Pro fresh from a USB stick and updated it.

Somehow I have a windows.old folder that has as user with the same username as I'm currently using on that laptop.

Anyone got any ideas wtf is going on as a quick google doesn't bring anything up.