1. Make sure box is turned OFF completely. I.e. Rocker switch in OFF position.
2. Turn on box with rocker switch and as soon as the front LED turns red put your finger on red button. Wait until it has blinked then release. You are now in rescue mode.
3. Download required firmware from dreamboxupdate.com
4. Use browser on PC to address webIf on DM520 (IP is shown on TV screen)
5. Use button 'install firmware' and point to download location on your PC..
6. Wait until flashing is complete and reboot box...