How to Triple Boot to Windows NT, Windows 95, and MS-DOS

• Microsoft Windows NT Workstation versions 3.5, 3.51, and 4.0
• Microsoft Windows NT Server versions 3.5, 3.51, and 4.0
• Microsoft Windows 95

SUMMARY

This article describes how to set up a computer so that the user can go directly to Windows NT, Windows 95, or MS-DOS by making a selection from the Boot.ini, without any need for Windows 95 multiple boot support.

MORE INFORMATION

This information applies to x86 processors only.

Follow these steps to enable triple boot support:

1. Install MS-DOS

2. Install Windows NT

3. Remove the read-only and hidden attributes of Bootsect.dos by typing and running the following line from the command prompt:

   attrib -r -h bootsect.dos

4. Copy the boot sector for MS-DOS by typing and running the following line from the command prompt:

   copy c:\bootsect.dos c:\bootsect.sav

5. Boot to MS-DOS and install Windows 95.

6. Repair the Windows NT boot sector as Windows 95 has over-written the boot sector. This will also create a new Bootsect.dos for Windows 95.

   For additional information, please see the following article in the Microsoft Knowledge Base:

   ARTICLE-ID: Q104429

          TITLE     : Installing MS-DOS Version 6.2x After Windows NT is
                      Installed
   
   

7. Remove the read-only and hidden attributes from the Windows 95 Bootsect.dos by typing and running the following line from the command prompt:

   attrib -r -h bootsect.dos

8. Rename the Windows 95 boot sector from c:\bootsect.dos to c:\bootsect.w40.

9. Rename the MS-DOS boot sector from c:\bootsect.sav to c:\bootsect.dos.

10. Remove the read-only attribute from boot.ini by typing and running the following line from the command prompt:

    attrib -r boot.ini

11. Modify Boot.ini using any text editor, such as Edit or Notepad, by adding the following lines:

    [Operating Systems] c:\bootsect.dos="MS-DOS v6.22" /win95dos c:\bootsect.w40="Windows 95" /win95

The new switches, /win95dos and /win95, are needed so that Windows NT can emulate the multiple boot process of Windows 95.

This article contains information about using Windows NT with a configuration that has not been tested and is not supported by Microsoft. If the steps described in this article do not function properly, use a supported configuration.

If Windows NT is going to be on the same partitions as MS-DOS and/or Windows 95, the partition must be an MS-DOS partition. Windows 95 FAT 32 partitions will not work with MS-DOS and Windows NT.

Using NTFS or FAT32 partitions will require different partitions for each operation system. The ARC path in the Boot.ini file will need to be modified to reflect the different partitions. For additional information, please see the following article in the Microsoft Knowledge Base:

   ARTICLE-ID: Q153762
   TITLE: Setting Up Dual Boot After Installing Windows NT