Microsoft DOS sys command

Quick links

About sys
Availability
Syntax
Examples
Additional information

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.

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

Availability

The sys.com command is an external command and is available in

All Versions of MS-DOS
Windows 95
Windows 98
Windows NT

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 the files are to be copied to.

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 sys.com file must be ran 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 ran 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 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.