DRIVER.SYS--Examples To add an external 720K drive to your system, add the following line to your CONFIG.SYS file: device=driver.sys /d:2 Since no location is specified, MS-DOS searches for DRIVER.SYS in the root directory of your startup drive. Suppose you want to use a single 1.44-megabyte external disk drive to copy files from one floppy disk to another. To do this, you must add two identical DEVICE commands for DRIVER.SYS in your CONFIG.SYS file. This procedure assigns two logical drive letters to the same physical drive. You can then swap disks in the same drive during the copying process. The following example shows how to do this: device=driver.sys /d:2 /f:7 device=driver.sys /d:2 /f:7