The problem is solved. One may simply turn off the Screen Lock by choosing "None" under Lock Screen Security.
1. At the Home screen, touch the All Apps button.
2. Open the Settings app.
3. Choose Security.
4. Choose Screen Lock.
5. If a screen lock is already set, you must trace the pattern or type the PIN or password to continue.
6. The Choose Lock Screen window lists six types of lock settings:
? None: The screen doesn?t lock. Even the Unlock-button-and-locking-ring thingy doesn?t show up. Choosing this option disables all locks.
? Slide: The Nexus 7 simply uses the standard locking screen: Slide the Unlock button to the unlocking ring.
? Face Unlock: Use the front camera on the Nexus 7 to use your adorable face as the unlocking mechanism.
? Pattern: To unlock the tablet, you must trace a pattern on the touchscreen.
? PIN: The Nexus 7 is unlocked by typing a personal identification number (PIN).
? Password: You must type a password to unlock the Nexus 7.