Release the button when the upgrade progress bar appears on the screen.
Once the update reaches 100%, the TV will restart. Unplug the USB drive immediately to prevent a restart loop. Where to Find Files
Use a high-quality USB drive (formatted to FAT32).
Hold the on the TV (not the remote) and plug the TV back in.
Often pre-configured for Samsung-style or M90 remote controllers. Operating System: Android 4.4 or higher. Memory: Usually 512MB RAM and 4GB ROM. Installation Guide