1.Remove battery and insert battery back.
2.Press and hold ‘VolumeUp’ and ‘VolumeDown’ keys.
3.Please insert USB cable within 60 seconds.
>>Analysis of USB port,Please insert phone USB cable.
>>Phone found[SCI USB2Serial (COM35)]
>>Internal version: SPRD3
>>INFERNO SPRD 773X bootloader v5.0
>>Clear FRP Success
>>Wait until the phone boot up.
If the phone does not boot up automatically,open it manually.
Thanks Volcano TeaM