You should reset your system when the device stops responding or appears to be "frozen" or "locked up＂.
To reset your system, press the Reset button on your device.
If your device still does not respond after being reset, you can use the following steps to clear the memory, and reset the system settings to factory defaults.
Disconnect all cables, including the AC Adaptor, from your device.
Use the stylus pen or your finger to slide the ON/OFF switch to the OFF position
Wait for 1 minute and then slide the switch back to the ON position.
Your device will automatically turn on and the Main screen will appear.

Note: Once you clear the memory with this ON/OFF switch, all the settings you have changed in the System Settings will be erased, you need to re-enter any personal settings, including time and date once again.

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