There are two ways to install the firmware. We recommend the method as it is safer and works even if the box won't boot fully.
This guide explains where to find and how to download the Android 7.1 stock firmware for MXQ Pro 4K TV Box (Amlogic S905 / S905W / S905X variants), what files/tools you’ll get, and safe flashing options and precautions. download android 7.1 stock firmware for mxq pro 4k tv box