P:\test>help subst Associates a path with a drive letter. SUBST [drive1: [drive2:]path] SUBST drive1: /D drive1: Specifies a virtual drive to which you want to assign a path. [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.