Download this Sandisk utility : U3 - Link : http://u3.sandisk.com/
The U3 Launchpad password feature enables you to password-protect the mass storage domain (drive letter) of your U3 smart drive. After enabling password protection you can only access your U3 smart drive by entering the correct password when logging in. When you define the password you can also, if required, enter a password hint, which can be used to assist you in the event that you forget your password. This password hint should be cryptic enough to give you an indication of what the password is, and should not make the password obvious to anyone else.