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Article ID: 122857 - Last Review: November 1, 2006 - Revision: 2.1

This article was previously published under Q122857
3.50 3.51 4.00
The RDISK utility included with Windows NT version 3.5 or later has two command line options:




When you use the RDISK /S option, the program skips the initial Create Repair Disk? dialog box and goes directly into saving the configuration.

When you use the RDISK /S- option, the program also skips the Create Repair Disk? dialog box, saves configuration, and then the program quits.


Both of these options also overwrite the saved SAM._ and SECURITY._ registry hives created during initial Windows NT Installation. The default administrator account and password used during Setup is all that is contained in these small files.

If you choose either of the above optional switches - Rdisk copies the entire current SAM and SECURITY database files containing ALL users and groups into the repair directory. On a domain controller containing many hundreds or even thousands of users these files can become very large which will Inhibit the ability to copy them to the emergency repair diskette (ERD).

Be sure you have enough disk space when using either of these switches on Windows NT Machines and Domain Controllers that have a large number of users and groups defined.

As a precaution - you should make a backup copy of the %systemroot%\repair directory to ensure you will still be able to make an emergency repair diskette after running RDISK while using one of the above switches.

  • Microsoft Windows NT Workstation 3.5
  • Microsoft Windows NT Workstation 3.51
  • Microsoft Windows NT Workstation 4.0 Developer Edition
  • Microsoft Windows NT Server 3.5
  • Microsoft Windows NT Server 3.51
  • Microsoft Windows NT Server 4.0 Standard Edition
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