If your Android tablet is not working or you just want to reinstall the operating system, follow these steps:

  1. Turn off your tablet and disconnect any cables.
  2. Boot into “recovery mode” by pressing and holding down the power button and volume down button at the same time until you see a message on the screen saying “Android is upgrading… please wait.”
  3. Once in recovery mode, use the volume buttons to scroll to “wipe data/factory reset” and press power button to select it.
  4. Press wipe data/factory reset again to confirm.
  5. Select install from sdcard and choose the ROM file that you want to install (for example, Android 7 Nougat).
  6. Press install and wait for the tablet to finish installing the new operating system. ..