No matter what version of MS-DOS or Windows you are using, you can create a bootable diskette. The following steps create an MS-DOS boot sector that loads IO.SYS and MS-DOS.SYS upon booting to the floppy.

The Result

You have a bootable floppy diskette. If the diskette is for an infected system, make it write protected before using it!

The 'Ingredients'

1. Access to a virus-free system with an appropriate floppy drive.
   If the bootable diskette is for an infected system, the virus-free system must be running the same version of MS-DOS or Windows 9x.
   (Problems arise when mixing versions of the operating system!)
2. A virus-free, non-write-protected floppy.

The Process

For MS-DOS 3.3 or 4.0

1. Insert the floppy diskette into the appropriate floppy drive.
   For the rest of these instructions, Drive A:\ is used. If the drive you are using IS NOT Drive A:\, you must substitute the correct drive letter for a.
2. At the DOS prompt, type:
   sys a:
   The system copies IO.SYS and MSDOS.SYS to the floppy.
3. When the system returns to the DOS prompt, type:
   copy command.com a:
   The system copies COMMAND.COM to the floppy.

For MS-DOS 5.0 and Later

1. Insert the floppy diskette into the appropriate floppy drive.
   For the rest of these instructions, Drive A:\ is used. If the drive you are using IS NOT Drive A:\, you must substitute the correct drive letter for a.
2. At the DOS prompt, type:
   sys a:
   The system copies IO.SYS, MSDOS.SYS, and COMMAND.COM to the floppy.

For Windows 9x

1. Insert the floppy diskette into the appropriate floppy drive.
   For the rest of these instructions, Drive A:\ is used. If the drive you are using IS NOT Drive A:\, you must substitute the correct drive letter for a.
2. Secondary click (for most users this is a right click) on
   3½ Floppy (A:)
3. Select
   Format... from the short cut menu.
4. Select
   Copy system files only
5. Select
   Start
   The system copies IO.SYS, MSDOS.SYS, and COMMAND.COM to the floppy.

Note: This bootable diskette DOES NOT boot Windows 9x into safe mode. This bootable diskette boots the system into real mode MS-DOS.