How to Create a Bootable Floppy in MS-DOS 6.22

Creating a bootable floppy diskette in MS-DOS 6.22 is accomplished primarily using the FORMAT command with the /S switch, or alternatively by using the SYS command on an already formatted disk. This guide outlines the exact syntax required for both methods, explains how they copy the core operating system files (IO.SYS, MSDOS.SYS, and COMMAND.COM), and details the steps necessary to generate a working startup disk.

The Primary Method: FORMAT with the /S Switch

The standard command to prepare a new or blank floppy diskette and make it bootable in MS-DOS 6.22 is:

FORMAT A: /S

(Replace A: with B: if your floppy drive uses a different letter.)

How It Works:

  1. Formatting: The FORMAT utility creates tracks and sectors, erases any existing data, and checks the diskette surface for bad sectors.
  2. System Transfer: The /S (System) switch instructs MS-DOS to automatically copy the three essential boot files from the current boot drive to the floppy disk:
    • IO.SYS: Handles the hardware interface.
    • MSDOS.SYS: The core DOS operating system kernel.
    • COMMAND.COM: The default command-line interpreter.

Once the process completes, the command prompt prompts for an optional volume label. After pressing Enter, the floppy diskette is ready to boot.

The Alternative Method: The SYS Command

If the floppy disk is already formatted and contains files you do not wish to erase, you can make it bootable using the SYS command:

SYS A:

Alternatively, specify the source drive followed by the target drive:

SYS C: A:

How It Works:

The SYS command transfers IO.SYS, MSDOS.SYS, and COMMAND.COM onto the target diskette without modifying or deleting other existing files, provided there is enough contiguous free space at the beginning of the disk's data area to accommodate the system files.

Optional: Adding Essential Utilities

A bare bootable disk created by FORMAT /S or SYS boots directly to a basic A:\> prompt. To make the disk functional for system recovery or maintenance, manually copy useful DOS utilities from C:\DOS onto the diskette, such as:

  • FDISK.EXE (Partitioning utility)
  • FORMAT.COM (Formatting utility)
  • HIMEM.SYS (Extended memory manager)
  • EDIT.COM (Text editor)
  • CONFIG.SYS and AUTOEXEC.BAT (Basic startup configuration files)

To test the diskette, insert it into drive A: and restart the computer, ensuring the system BIOS is configured to boot from the floppy drive first.