My Blackberry TV demonstrates how to protect your Blackberry device with a password. Protecting your Blackberry with a password will help to stop people from accessing your personal information on your device. From the home screen, press the Blackberry menu key. Then, select the options choice. Next, scroll down to the password choice on the options menu. Select password and then select the set password button on the password screen. Enter your desired password and then press the enter key. Verify the password by retyping it and pressing enter again. Your password will now be set on your Blackberry device. Hold down the A key to lock your Blackberry.