- Confirm and make sure that LENOVO A800 Battery is fully charge or not empty
- Turn off LENOVO A800
- Press together : POWER + VOLUME UP about several second, that the warning will appear at the LENOVO A800
- Choose: Reset Device or Wipe data or Clear eMMC
- Make sure we already sure than we know that our application and data will be loose or clear while Resetting LENOVO A800
Please remember, doing hard reset with master reset to factory default above will make all important data and installed applications will be removed and wipe from LENOVO A800, so you have to backup all important data