Just identified that Windows 10 Creators Update can format Internal HDD, external HDD using ReFS file system without any registry hack. What's more interesting is, despite all the current documentation saying that UFD could not be formatted with ReFS, I just successfully did on a 8GB UFD on my computer. It also appears you could format a single volume HDD/UFD device without any logical volume mirrors. Could not find any further documentation of this feature in Creators Update. Anyone has further ReFS information for Creators Update?