About subst
Allows you to substitute a folder on your computer for another drive letter.Availability
The subst.exe command is an external command that is available in the below Microsoft operating systems.MS-DOS 3.1x and above
Windows 95
Windows 98
Windows ME
Windows NT
Windows 2000
Windows XP
Windows Vista
Windows 7
Syntax
Associates a path with a drive letter.SUBST [drive1: [drive2:]path]drive1: Specifies a virtual drive you want to assign a path.
SUBST drive1: /D
[drive2:]path Specifies a physical drive and path you want to assign to a virtual drive.
/D Deletes a substituted (virtual) drive.
Type SUBST with no parameters to display a list of current virtual drives.
Examples
subst a: .Sets the directory you are in and subdirectories thereafter into the A: drive. So if you were to type A: after doing this command you would see everything in the directory that you typed this command in.
If you were to reboot your computer this will clear the SUBST command and put your drives back to original letters (unless command placed into the autoexec.bat).
Tip: You cannot subst network drives and after a drive has been created you cannot give the new drive a new label.