Microsoft DOS sys command

Updated: 05/21/2018 by Computer Hope

About sys

Sys is used to copy the system files from one drive to another drive, allowing that drive to be bootable.

When running sys, the below files will be copied.


The sys command is an external command and is available in the below Microsoft operating systems as

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 this from c drive and you have a formatted disk in the drive, this would copy the system files to that disk making that disk bootable.

Additional information

The file must be running on the drive that contains the system files and the 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 all the necessary files are on that diskette.

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