How To Make a Dos Boot Disk
Level of difficulty:
The boot disk was introduced into the computer industry during the time when computer systems (particularly home desktop machines) did not have hard drive storage and relied mostly on programs that were running from floppy disks which included among other things the MS-DOS Operating System platform. With the introduction of hard drive storage features as well as the proliferation of Graphical User Interface (GUI) based Operating System environments, the boot disk was relegated to the background as an alternative way of preparing the machine for use. In other cases, the boot disk came into play when preparing to install an Operating System into the hard drive or attempting to troubleshoot other problems being experienced by the machine. Initially, boot disks referred specifically to floppy disks that contained the system files, however, when optical media was introduced, there were several authoring tools that incorporated the functionality of creating boot disks on CD or DVD media.
- Computer with MS-DOSsystem
- Floppy disk
- CD or DVD media
- Floppy drive
- CD or DVD drive
- Nero Burning ROM
To create a boot disk on a CD or DVD drive, jump to step 8. To use a floppy disk, proceed to the next step.
On the command prompt, type cd\dos to navigate to the DOS folder where the system files are stored.
Once in the correct folder, type the command FORMAT A:/S which will essentially remove all contents of the floppy drive and copy all necessary system files. This command works for MS-DOS 6.2 as well as Windows 3.x up to Windows 98.
After the system has been successfully transferred to the floppy disk, you need to copy system tools. Type copy format*.* a: and then press the Enter key. Repeat the copy process by replacing format *.* with fdisk*.*, mscdex*.*, sys*.*, edit*.*, qbasic*.*, debug*.*, himem*.*, and emm386*.* respectively.
The next stage is to create an autoexec.bat file which will be read and executed on system boot up. At the command line, go to the drive A and type 'copy con autoexec.bat' and press the Enter key. Key in @echo off and press Enter. Type LH A:\MSCDEX.EXE /D:CDROM followed by the Enter key. Simultaneously press the CTRL key and the Z key which will display ^Z on the screen. Press the Enter key to save the file on the floppy disk.
Another required file is the config.sys. Still from the A: prompt, type in copy con config.sys and press the Enter key. The device=a:\himem.sys, dos=high,umb, device=a:\emm386.exe noems, files=30, buffers=20, devicehigh=a:\oakcdrom.sys /d:CDROM commands must be typed in respectively on separate lines followed by the Enter key. Press and hold the CTRL and Z keys to save the file.
The bootable disk is now complete. The last step is to make sure that the floppy disk is write protected to prevent intentional or accidental overwriting of the stored files.
To create a bootable disk using a CD or DVD media, you will a utility program like Nero Burning ROM. If installed in your machine launch the application.
From the wizard, simply select the Bootable Data Disk option. Make sure that the correct drive is chosen and click on the Next button.
The software will proceed to create an MS-DOS bootable disc based on the current system files of the host machine. When completed, the CD or DVD media will be ejected.
Label the optical media accordingly to finish the creation process.