Type: External (5.0 and later)
Purpose: Deletes all files from previous versions of DOS after a 5.0 or 6.0 installation.
During an upgrade installation of DOS 5.0 or 6.0, your previous version of DOS is stored in a directory named OLD_DOS.1 and on uninstall disks created by the DOS Setup program. After you have finished installing and testing the new version of DOS, you can delete your old version of DOS by using the DELOLDOS command. Once you have used the DELOLDOS command, you will not be able to restore your previous version of DOS from the Uninstall disks so be sure that the new version of DOS works on your computer before using this command. Also, the DELOLDOS command will delete itself from your disk once it has finished deleting your old version of DOS.
/B – Specifies a black-and-white screen mode. Used with LCD displays or when using a monochrome monitor attached to a CGA adapter.