MacBert

I have the exact same problem. In my case i have put the once OS drive into an external box which mounts as D: but is not readable by the OS. I ran a deep scan for pictures (though pictures and video would have been a nice option to combine), it ran overnight but the PC went to sleep. When I woke it up, the drive light shows it's active and i also power cycled it after getting the message above. No previews shown for any pictures. Using up to date Windows 10.