SUBST is a great DOS command that allows you to map a local path to a drive letter. For example, wouldn’t it be easier to access you GAC folder by specifying G: instead of C:\windows\assembly?
The SUBST command is very easy to use. Simply open up a command prompt window and type:
“SUBST G: C:\windows\assembly”
Now when you go to Windows Explorer or My Computer you will see a new drive with a label of G: Open the drive and you are looking at the contents of C:\windows\assembly
You could do this for any path on your PC with the syntax being…
SUBST drive: path Any Folder
When you type the SUBST command into a Command Prompt window, you will lose the virtual drive when you restart your system, so a better way to make the virtual file would be to put the SUBST command into a batch file that lives in your Startup folder. Now every time you start your PC, the virtual drive will be there.
Virtual Drive Creator is a free program that will create the virtual drive from a GUI, thus saving you from the dreaded Command Prompt. The program is free, but they do offer a better version with more features for a small registration fee.
To Delete the virtual drive: SUBST drive letter: /D