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Q101789: Reconstructing BOOTSECT.DOS

Article: Q101789
Product(s): Microsoft Windows NT
Version(s): 3.1 3.5 3.51 4.0
Operating System(s): 
Keyword(s): kbsetup
Last Modified: 08-AUG-2001

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The information in this article applies to:

- Microsoft Windows NT Server version 3.1 
- Microsoft Windows NT Workstation version 3.1 
- Microsoft Windows NT Advanced Server, version 3.1 
- Microsoft Windows NT Workstation versions 3.5, 3.51, 4.0 
- Microsoft Windows NT Server versions 3.5, 3.51, 4.0 
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Bootsect.dos is created by Windows NT Setup. The boot sector found in
sector 0 of drive C is copied into Bootsect.dos before Setup writes the
Windows NT boot sector. (Setup will not overwrite an existing
Bootsect.dos.) If you choose a previous operating system, Windows NT
executes Bootsect.dos, simulating the previous operating system's normal
boot procedure.

Because the information in Bootsect.dos is really created by the previous
operating system, it is very difficult to re-create. You must transfer the
BIOS parameter block (BPB) from the boot drive (C) at sector 0 into the
boot code from the previous operating system and write this into
Bootsect.dos. To do this, use the following procedure:

1. Use the proper utility to regenerate a boot sector for the previous operating
  system. For example, if the previous operating system is MS-DOS, boot MS-DOS
  from a floppy disk and run the SYS C: command.

2. Start Windows NT Setup from the boot floppy disk (this may be disk 1 of the
  Windows NT floppy disk set, the boot floppy disk for the Windows NT CD-ROM,
  or may have been created during a setup using WINNT.EXE), and initiate
  repairs by pressing R at the first Setup screen.

3. Follow the instructions provided by Setup. When Setup presents you with the
  list of optional repair tasks, make sure you have enabled the "Verify boot
  files on your C: drive" item.

4. Follow instructions until you see a message stating "Setup Repair is
  complete."

Bootsect.dos should now be restored to its original state. You should be
able to boot your previous operating system.

Additional query words: prodnt tshoot repair \\bootss
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Keywords          : kbsetup 
Technology        : kbWinNTsearch kbWinNTWsearch kbWinNTW400 kbWinNTW400search kbWinNT351search kbWinNT350search kbWinNT400search kbWinNTW350 kbWinNTW350search kbWinNTW351search kbWinNTW351 kbWinNTW310 kbWinNTSsearch kbWinNTS400search kbWinNTS400 kbWinNTS351 kbWinNTS350 kbWinNTS310 kbWinNTAdvSerSearch kbWinNTAdvServ310 kbWinNTS351search kbWinNTS350search kbWinNTS310search kbWinNT310Search kbWinNTW310Search
Version           : 3.1 3.5 3.51 4.0

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