MS-DOS and Windows command line sys command

Updated: 04/02/2019 by Computer Hope
sys command

The sys command is used to copy the system files from one drive to another, allowing the second drive to be bootable.

Note

When running sys, the following files will be copied:

command.com
io.sys
msdos.sys
drvspace.bin

Availability

Sys is an external command that is available in the following Microsoft operating systems as sys.com.

Sys syntax

Copies MS-DOS system files and command interpreter to a disk you specify.

SYS [drive1:][path] drive2:
[drive1:][path] Specifies the location of the system files.
drive2: Specifies the drive to which the files will be copied.

Sys examples

sys a:

If you type text while in the C: drive and you have a formatted disk in the drive, it would copy the system files to that disk and make that disk bootable.

Additional information

The sys.com file must be running on the drive that contains the system files and the sys.com file. If you're running from the hard drive, this command is commonly located in the C:\Windows\COMMAND\ directory on Windows 95, 98, NT, and 2000 or in C:\DOS\ directory on Windows 3.x / DOS. This command can also be run from a bootable diskette assuming that it contains all the necessary files.

If, when booting your computer, you get "Missing command interpreter," this could be an indication of missing command.com. To resolve this issue, boot from a disk that has sys.com and command.com on the disk, type sys c: from the A:\>, remove the disk and reboot the computer.