The NTFS file system stores its database of mounted devices in the MountedDevices subkey. This database associates persistent volume names with unique internal indentifiers for volumes. The internal identifier often includes the disk signature of the volume. This pairing enables NTFS to maintain the identity and persistent name of a volume, even when its variable device name changes.
NTFS uses the MountedDevices subkey to support mounted drives on all types of volumes, including removable drives and CD-ROM drives.
The MountedDevices subkey replaces the HKLM\System\Disk subkey used in Windows NT 4.0 and earlier. However, its contents and use are changed for Windows 2000.