If your device hangs then it probably means that its Operating System is upset/corrupted. To correct this you will need to perform a hard reset (All user data and files will be erased). The following describes how a hard reset is to be performed.
1. Press and hold Volume up and Back button and the Power button (all three at once and keep all of them held down) for 30 seconds.
2. Release all the buttons as soon as the Android logo pops up - Now you are in Recovery Mode
3. You may have to Press the Back button to see the options
4, Use the Volume keys to navigate with to and select "Wipe all data/ Factory Reset" option "
5. The device will now perform factory reset and reboot. As soon as it starts up, it is back to it`s fresh factory state (You may have to manually select "Reboot Now" after the hard reset process is completed.
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