If you want to Map a fake drive letter to a folder you have use subst command.Use the SUBST command to substitute a drive letter for a path in order to treat a virtual drive (a reserved area rather than an actual disk drive) as a physical drive.
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.
1) To create a virtual drive F for the path, SALES\LETTERS (under the root directory) of drive C, enter
subst f: c:\sales\letters
Read and write requests to either drive F or to C:\SALES\LETTERS will be stored in the C:\SALES\LETTERS d
2 ) subst N: C:\windows
now if you enter in N: you will see the Windows folder’s contents. This is done on a per-user basis (every user can have its N: pointing to a different directory) and it disappears on the first reboot.
Make it Permenent
If you want to have it permanent, there is a hidden trick, creating a new key in the registry.You have to go to
HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\DOS Devices
and there create a key named with the drive letter you want, colon included (f,N: in our example) and with this value:
you can obviously change c: and windows for whatever folder you want, but remember to double the backslash after the unit letter, because it won’t work with a single backslash.
Six DOS commands cannot be used with virtual drives created with the SUBST command. They are: