Android TV box Firmware Guide
Put your device into recovery mode and connect to your PC
You will have to put your device in recovery mode, this will depend on each device since it is different in all TV Boxes. Some have small reset holes, and others have buttons on the bottom of the device. You must connect your Android TV Box to your PC when in recovery mode to update its firmware. If done correctly, you will have a connection success as seen in the image above.