Normally for getting the dual boot option in Windows, we will first install the lower
version of Windows then higher version. But if we are trying to dual boot MS DOS 6.22
and MS Windows Vista business, DOS will not boot. This is due to during the
installation of Windows Vista, it will corrupt the boot sector entries of DOS, hence only
Windows Vista will boot.
We will able to dual boot MS DOS 6.22 and Windows Vista business. Refer the
below said procedure for more details

Requirements:

Operating Systems:
1) MS DOS 6.22 floppies
2) Windows Vista Business 32 bit CDs

btsect25.zip (ver 2.51):
Thiis zipped file contains 3 files named BTSECT.BAT, bootread.scr, BTSECT.TXT. BTSECT.BAT creates a new C:\bootsect.dos from the current C: sector.
It runs in from your DOS boot disk, or Startup Disk.
You can also down load the same from the below said link
http://www.thpc.info/dual/bootsectdos.html

EasyBCD (ver 1.7.2):
Here by I have attached one copy of EasyBCD.exe file in mail body. EasyBCD is an
advanced GUI application that makes it easy to modify the Windows Vista boot loader
and the entries in it.
You can also down load the same from the below said link
http://neosmart.net/dl.php?id=1

Creating bootable MS DOS Startup disk with btsect files.:

After installing the MS DOS 6.22 in the machine, copy the contents of btsect25.zip
file into MS DOS 6.22 DISK1 for creating startup disk. And also copy the file
CHOICE.COM to disk 1 from C:\DOS by using the below said command.
C:\DOS\>copy choice.com a:
(Ensure to keep the MS DOS 6.22 disk 1 in FDD)

Phase -1 MS DOS 6.22 Installation:
1) Install MS DOS 6.22 in 2 GB partition

Phase -2 Installing BTSECT.BAT:

1. Boot the machine by using the MS DOS Startup disk you have created. MS DOS
   setup will begin. Press F3 twice after it loads up to exit setup. Now you will get
   A:\
2. Run BTSECT.BAT file from A: drive. This stores a copy of the current
   bootsect.dos on the root directory of the C: drive
   A:\>BTSECT
3. At the Read the help file (BTSECT.TXT [Y/N])? Type Y or N as per your
   requirement
4. At the Create a new bootsect.dos now[Y/N]?Type Y
5. At the Press any key to continue! Press Enter Key
6. At the Use SYS C: command[Y/N]?Type Y
7. At the Restore original system boot files[Y/N]? Type Y
8. At the Read dual boot repair help[Y/N]? Type Y or N as per your requirement
9. At the Exiting. Finished Reading[Y/N]? Type Y

Phase -3 Installing Windows Vista Business 32 bit

1. Install Windows Vista business to a new NTFS partition. (Make sure you do not
   alter the FAT16 DOS partition.)
2. After the installation, you will able to boot in to Windows Vista. Note, now you
   will not get dual boot option and will not able to boot in to DOS. But inside the
   Windows Vista, you will be able to see the D: drive partition, which is our DOS
   partition.

Phase -4 Installing EasyBCD in Windows and adding MS DOS boot entry.

1. Enter into Windows vista.
2. Install Easy BCD. At the Welcome screen click Next.
3. At the License Agreement screen, click on I Agree
   
   
   
4. At the Choose components screen, Click on Install

5. At the Completing the Easy BCD setup Wizard screen, Click on Finish.


6. EasyBCD will run automatically (Or you can run it from the shortcut created on
   desktop). Click on Add/Remove Entries to add the boot entry for DOS

7. You will get the below said screen.


8. Under Add an Entry tab, Change the below said
   Type as Windows 95/98/ME
   Name as MS DOS 6.22
   Drive as D:\
   And then click on Add Entry. You will get the bellow screen. Click on
   save to save the entries.

Restart the machine. Now your machine is capable to dual boot. Use arrow keys
to highlight your choice.
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