NT signature

When the MBR is selected along with the disk backup, you need to retain operating system bootability on the target disk volume. The operating system must have the system volume information (e.g. volume letter) matched with the disk NT signature, which is kept in the MBR disk record. But two disks with the same NT signature cannot work properly under one operating system.

If there are two disks having the same NT signature and comprising of a system volume on a machine, at the startup the operating system runs from the first disk, discovers the same signature on the second one, automatically generates a new unique NT signature and assigns it to the second disk. As a result, all the volumes on the second disk will lose their letters, all paths will be invalid on the disk, and programs won’t find their files. The operating system on that disk will be unbootable.

To retain system bootability on the target disk volume, choose one of the following:

  • Select automatically

    A new NT signature will be created only if the existing one differs from the one in the backup. Otherwise, the existing NT signature will be kept.

  • Create new

    The program will generate a new NT signature for the target hard disk drive.

  • Recover from backup

    The program will replace the NT signature of the target hard disk with one from the disk backup.

    Recovering the disk signature may be desirable due to the following reasons:

    • Acronis Backup & Recovery 10 creates scheduled tasks using the signature of the source hard disk. If you recover the same disk signature, you don’t need to re-create or edit the tasks created previously
    • Some installed applications use disk signature for licensing and other purposes
    • This enables to keep all the Windows Restore Points on the recovered disk
    • To recover VSS snapshots used by Windows Vista’s “Previous Versions” feature
  • Keep existing

    The program will leave the existing NT signature of the target hard disk as is.

NT signature