Encrypted WD Target Removing or Changing Password
If you wish to change or remove the password on your WD encrypted target drive you will need to install the WD Security Utility. From there you will be able to change or remove the password. You can download this from their website. Here are links to the most common drives, but confirm with WD's website to make sure you have the correct utility for your model of drive.
For the My Book
http://support.wdc.com/product/download.asp?level1=1&lang=en
For the Passport
http://support.wdc.com/product/download.asp?level1=2&lang=en
If your intention is to reinitialize the drive deleting all the data and to clear the password, then the easiest way to do this is to put in the wrong password until you are given the option to erase the drive. This will initialize the drive to the format of the computer that you are on and clear any passwords that are set. Note: This is destructive and all data will be lost and unrecoverable.