If you've encrypted the drive, it will only work in its enclosure.If you lose the password, even WD won't be able to help you regain access to the drive.Once the drive is unlocked, it will appear under Hard Drive Devices. Open this drive by double clicking on it and then double click "WD Drive Unlock". This is a partition on the My Book drive that contains the software that will allow you to unlock the drive. If you aren't, open My Computer and look for a CD drive called "WD Unlocker". If you set the security password on the drive, you will be prompted for it if you connect the drive to a different computer.The user manual is on the My Book drive in \User Manuals\ENG\UserManual.pdf.