Welcome to the Community,
growing of a thin provisioned virtual disk is usually caused by some guest OS (guest file system) actions. However, I can't unfortunately tell you what exactly is going on.
Some question though if you don't mind:
- does this occur at some specific day of the week, and/or at certain time?
- which Windows version, and build do you use?
- which file system is in use (NTFS/ReFS)?
André
