If you are a former Home Server, now Windows 2012 Essentials using storage spaces, make sure you install the June update rollup.
In it, it includes a hotfix that sounds like a lot of fact patterns I’ve seen discussed.
Storage space cannot be repaired or disks are marked as retired incorrectly when you use Storage Spaces in Windows 8 or in Windows Server 2012:
It’s included in this update:
Windows RT, Windows 8, and Windows Server 2012 update rollup: June 2013: