1909

One partition suddenly inaccessible-ptneinaccessible.jpg

diskmgmt.msc also showed it to be healthy.

diskmgmt.msc's properties was the only thing that revealed that all permissions were gone!.

I was able to create ("Add") permissions in the properties' Security tap. Problem solved.

I am writing to ask whether anyone ever has encountered disappearance of all permissions
to a partition. I never had.