Step as below:
1. Open iTunes.
2. Plug iPad to your computer via USB cable.
3. Hold the "Home" button and the "Power" button on the top side of iPad until the iPad screen goes black. When the Apple logo appears, release the Power button and continue to hold down the Home button. At that time, your iTunes will pop up a window showing you your new iPad needs to be restored.
4. Follow the instruction which your iTunes tells and download the latest firmware.
5. Restore firmware on your iPad then.
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