Microsoft DOS assign command

Updated: 05/21/2018 by Computer Hope

About assign

Introduced with MS-DOS 2.0 and has been available up to 6.0 where it was removed because of concern with data issues. Was latter made available on the MS-DOS 6.0, 6.2, and 6.22 supplemental disks. The assign command redirects disk operation on one drive to a different drive.

Note: Any users using Windows 95 or above should not use this command and consider using the subst command as a substitute.


The assign command is an external command file named and is available in the below Microsoft operating systems as

Assign syntax

ASSIGN Source = Target /status

ASSIGN Assign with no switches cancels redirected drive assignments and sets them back to their original drives.
Source Letters of source drives.
Target Letters of target drives.
/status Lists current drive assignments.

Assign examples

Note: The assign command does not work with format, diskcopy, diskcomp, backup, label, restore, print or subst.

Warning: Do not use a colon after a drive letter in versions before 5.0.

assign a: = b:

Assigns the A: drive as the B: drive.

assign a =  b = c

Assigns A: as B: and B: as C:.