This command maps the Outlook folder stored at C:\Documents and Settings\username\Local Settings\Application Data\Microsoft\Outlook to a drive letter like Z.

If you click on the Z drive in My Computer, you’ll be redirected to the Outlook folder! This can be helpful if you’re working with paths that are longer than 256 characters. ..

The SUBST command is not persistent, meaning that when you restart the computer, your drive is gone. You have to create it again and you can’t have any startup program try to access the substituted drive since it’ll disappear.

Psubst is a nifty little program that you can use to create persistent substituted drives in Windows that will remain even after restarting. This can be useful if you need to keep a certain file or folder open across multiple sessions, or if you just want an extra layer of security. ..

To create a persistent virtual drive in Windows using psubst, first download the ZIP archive and extract the .BAT file. You can extract files in Windows by simply right-clicking on the ZIP file and choosing Extract All.

You can run the psubst.bat file from the command prompt by typing: C:\Windows\System32\psubst.bat

PS C:> psubst -d “C:" “D:" PS C:> psubst -d “C:\Program Files (x86)\Windows Kits\10\Insiders" “D:\Insiders" ..

Create a disk:

Delete a disk:

List of existing disks:

/P virtualdrive

Create a persistent virtual drive:

Delete a persistent virtual drive:

Z:\OutlookData
This would create a new folder called “Z” in the Outlook data folder. The new folder would be used as the virtual hard drive for your Outlook data. ..

Your new hard drive will now be listed as a local disk in My Computer. ..

If you click on the disk, Outlook will open in its default location. If you drop files or folders on the drive letter, the data will be copied to that folder.

If you restart your computer, your drive will be there and you can have other programs access it even before Windows starts up. It also shows up in places where Explorer is used like Open dialogs, Save as dialogs, etc.

Mapping a folder to a drive letter is a great way to access a very deep folder quickly and easily. You can obviously also create a desktop shortcut to your folder, but the substituted drive method has the advantage of being accessible from any Windows dialog that lets you browse the computer. If you have any questions, feel free to comment. Enjoy! ..