Making drives inaccessible

As an alternative to hiding a drive, you can opt to make it inaccessible so that an error messagw will pop up when the drive is double clicked.
Here's how to do that:

Go to the same key:

In the right hand pane for the Explorer key, create a new DWORD value named NoViewOnDrive

Double click the new value and use the same method as used for hiding drive icons to determine the decimal number to enter.

Once done, reboot or log off and login in again. Then try double clicking the drive you made inaccessible. You should receive a message stating that the drive cannot
be accessed.