yes turn of from the back switch it back on and hold the on/off button on the front in for a few secs at the same time you will then see the ip of the receiver on the led screen type that into your url, on the screen on the pc choose uprade firmware.
Follow the instruction from Brummie but use your router or switch to do this, it is important that network communications on the 800 and on your router are set to use DHCP or you will not get to the firmware flashing page all you'll get is the enigma 2 webif.