To hide your server hard disks, please proceed as following :
You can now select the drives you want to be hidden!
This tool works globally meaning that even the administrator will not have a normal access to drives after the settings have been applied.
Hiding the drives does not disable the access to them. It prevents the user from seeing them.
The tool flags the disks drives as hidden, and it also adds the HIDDEN property to the entire root folders and users list in Document and Settings.
If you need to completely restrict access to the drives, you will need to install and use RDS-Knight, available here: RDS-Knight.