>>Operation: 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 (COM69)] >>Internal version: SPRD3 >>Boot downloaded. >>INFERNO SPRD 773X bootloader v5.0 >>Boot downloaded. >>Factory reseting... >>Format success. >>FRP not found >>Wait until the phone boot up. If the phone does not boot up automatically,open it manually.