When Disk Administrator is run for the first time, it creates the key HKEY_LOCAL_MACHINE\SYSTEM\DISK . RAID and disk
characteristics are stored in this subkey. If you have a RAID controller which
supports extending the RAIDs volume size, the change will not be reflected in NT
until you delete the DISK subkey and start Disk Administrator. At this point,
since the DISK subkey does not exist, Disk Administrator will announce that this
is the first time Disk Administrator has been run and it will recreate the DISK
subtree with the updated characteristics.