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1. First we will delete all user data on the device. To do this, go to Settings from the home screen. Click on "Privacy" and then click on "Factory Data Reset."Go through the data reset process. This will remove all personal data from the device.
2. Now you need to enter the recovery console. To do this, hold both the silver return button on the front of the tablet AND the power button until you see the green Android robot standing next to a warning triangle. When you see these logos, let go of both buttons.
3. Press the silver return button by itself. The recovery menu should appear. To navigate the recovery menu, you use the home and menu buttons on the tablet. Home scrolls up and menu scrolls down.
4. Use the menu button to scroll down to "wipe data/factory reset." Use the silver return button to select this option. Another screen will appear. Use the menu button to scroll down to "yes -- delete all user data" and press the silver return button to select this option. The device will wipe the data and then it will return to the main recovery screen.
5. When it returns to the main recovery screen, "reboot system now" should be the option selected. Use the silver return button to select this option. The tablet will reboot.
That's it! This should return everything to an unmodified state.
Hope this helps. If you have any further question, feel free to ask.
