Using an Emergency Repair Disk Created by Windows NT

• Microsoft Windows NT Workstation versions 3.5, 3.51 and 4.0
• Microsoft Windows NT Server versions 3.5, 3.51 and 4.0

SUMMARY

During Windows NT installation, an Emergency Repair Disk (ERD) is created that includes the following:

System Registry hive    (SYSTEM._)

MORE INFORMATION

If something happens to your computer hard drive to corrupt or change your startup system files or NT Registry you can use the ERD to get the system back into a bootable state. After you are back into the Windows NT operating system – you can then perform a full recovery by restoring from your last system backup.

For Example: You have a Windows NT system that allows you to specify which operating system to start (MS-DOS or Windows NT) by using the boot loader menu. If the MS-DOS SYS command is inadvertently run on drive C, you will no longer be able to start (boot) Windows NT. You will only be able to start MS-DOS.

The boot loader is a small program that resides in the first physical sector[s] of the active partition. Windows NT stores the old boot loader code into a new file called BOOTSECT.DOS. Windows NT replaces the boot loader sector with a new loader program stub. This new loader finds the program NTLDR and executes it. NTLDR switches into protected mode operation and loads a mini-file system, which then reads BOOT.INI. BOOT.INI presents the boot loader information used to start your system with Windows NT or MS-DOS. In the above example, when the SYS command was run from MS-DOS, the boot loader sector was overwritten by MS-DOS's boot sector. This MS-DOS boot sector does not know anything about Windows NT or boot loader.

SAMPLE REPAIR PROCEDURE

The procedure below explains how to re-create the Windows NT boot sector information, allowing the dual boot features to be re-activated using the Emergency Repair Disk created during installation:

1. Start your system using Windows NT Setup Disk 1 then Disk 2.

2. At the first screen, press “R” for Repair.

3. You will see four selections. All four will be selected by default. Move the selector bar with the arrow keys to highlight the options. Use the ENTER key to select/clear the options.

   [ ] Inspect registry files [ ] Inspect startup environment [ ] Verify Windows NT system files [X] Inspect Boot Sector

4. Select only the option “Inspect boot Sector”. Move the selector bar to the line that says to Continue and press the ENTER key.

5. Let Windows NT perform the mass storage detection. If necessary select “S” to specify additional drivers if your machine requires OEM drivers.

6. When prompted to do so, insert the Emergency Repair Disk that was originally created for this computer. (Or hit escape to let NT search for 3.51 or 4.0 repair information)

7. Repair will run CHKDSK, verify the boot sector and rebuild if necessary.

8. You will be prompted to restart your machine when the process is complete.

ADDITIONAL SOURCES OF INFORMATION

For more information about using the Emergency Repair Disk, see:

ARTICLE-ID: Q129037

TITLED    : Windows NT 3.5x and 4.0 Emergency Repair Process Screens

TITLED    : How to Repair Windows NT System Files Without a CD-ROM

ARTICLE-ID: Q126464

TITLED    : Repair Disk Utility Does Not Update SAM and Security Hives

TITLED    : RDISK /S and RDISK /S- Options in Windows NT