So I’ve been having this mystery problem with Server 2012 R2 for a while now. I have a 2TB external drive that I am using for backup storage. I was running out of space on the drive, and I couldn’t figure out why. When I added up the files on the drive, they didn’t come anywhere near 2TB. In fact, I moved everything off of the drive entirely and I still had only 32 GB free! Something was definitely awry, and I had to figure out what.
My first thought was to just re-initialize the drive and go on with my life, but then I would always be left wondering what caused it. So instead I investigated until I found the problem, and hopefully this article will help someone else resolve the issue without having to shuffle tons of data around to re-initialize a drive.