Setting Up Dual Boot After Installing Windows NT

Last reviewed: November 11, 1997
Article ID: Q153762
The information in this article applies to:
  • 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

This article explains how to set up Windows NT to dual boot with MS-DOS on a computer that was originally installed as Windows NT only. In order to dual boot, the system partition must be a file allocation table (FAT) partition and not a Windows NT file system (NTFS) partition.

MORE INFORMATION

  1. Start the computer from an MS-DOS floppy disk that contains the sys.com you file. Sys the boot drive to MS-DOS using the following sys command:

          A:\>sys a: c:
    

    You should receive a system transferred message when this is complete.

NOTE: This will disable the Windows NT boot loader and now the computer will boot MS-DOS when booting from the computer's hard disk drive. You will have to repair the Windows NT boot loader after completing the procedures explained below.

  1. Reboot the system from the computer's hard disk drive to an MS-DOS command prompt and install MS-DOS on the system if it is not already installed.

  2. After completely installing MS-DOS onto the system and rebooting as necessary, restart your system using your Windows NT Setup disks. During Setup, select R to repair Windows NT.

NOTE: You only need to repair the Windows NT boot sector. You should not choose to inspect the registry files, the Windows NT system files, or the Windows NT boot environment during this procedure.

  1. Once you have repaired the Windows NT boot sector will need to manually edit the Boot.ini file to include an option to boot to MS-DOS. The Boot.ini file is a read-only, hidden, system file located in the root directory of the boot drive. The following line should be added to the Boot.ini file under the operating systems section:

          c:\="Microsoft DOS".
    

The next time you reboot the computer, you should have an option to choose Microsoft DOS on the Windows NT start menu.

The procedure above can also be used to enable dual booting between Windows NT and Windows 95. To dual boot Windows 95, boot the system to MS-DOS and install Windows 95. Windows 95 installation is Windows NT-aware and will not overwrite NT boot loader information when installed in this manner.


Additional query words:
Keywords : NTSrvWkst kbsetup
Version : 3.5
Platform : winnt


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Last reviewed: November 11, 1997
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