If using Microsoft® Exchange / Corporate sync, the option to turn off screen lock may be unavailable.
From a Home screen, tap Apps .
From the Apps tab, tap Settings.
Tap Lock screen.
Tap Select screen lock.
If presented with "This device does not have a Google account associated with it. If you forget your PIN, it cannot be sent to you and a factory reset has to be performed to recover the device.", tap Add Google account now to setup an account before proceeding. To proceed without setting up a Google account, tap Continue.
If presented, enter the current PIN, password or pattern.