1) Use small rs232 board connected to receiver and use rs232 cable connected to computer.
2) Power on the box
3a) Do Flash folder (update 1kb file)
3b) Run UpdateAllFlash.exe on PC and choose the correct com port
4) Open "solo boot.bin"
5) Click update, it will show progress, wait it to finish.
6) Remove small rs232 board and cable
7) Power off, and power on again, box will finally start/boot, now you can use usb, update the image you want with USB Stick