Drive characteristics for Storage Spaces

Going through Hell with Win10. Installed my dual 2TB drives, formatted them, and tried to create a mirrored Storage Space. System claimed "No drives that work with Storage Spaces are available." So I used the mirrored RAID system instead. But every folder I create is read-only and I've not been able to fix the issue.

So I'm back to wanting to try Storage Spaces. Does anyone know the requirements for the disks? Trying to figure out why Windows won't let me use these disks, even though they're identical, both newly formatted (not quick formatted), and were in a RAID array in my old HTPC/server.

Thanks

Finally figured out I had already formatted the drives and Storage Spaces requires disks with no partitions. Not sure why in hell Microsoft can't have SS identify the issue instead of just telling us the drives won't work.