Need to control access to wireless drive within home network

I have set the admin password to control the configuration of the My Passport Wireless Pro and I have set the control to prevent USB modifications to the drive as well. However, I need to have additional password security for when guests come to my home and I grant them network access but I do not want them to have access to My Passport Wireless Pro data. How do I have that additional security within a home network?

I believe this devices provides password protection for the user “shares” on the device. Just use a different password as your general network access.

It should act like any other NAS device on the network for which you don’t give out the password.