Installing image on a new Dreambox One Ultra HD

Hi

I've bought a dreambox one ultra hd receiver and downloaded image newenigma2. I switch off decoder from the rear button, switch on again and quickly hold the power button until tv shows ip address of the decoder. But instead of the ip address, the tv shows the message "RESCUE MODE Waiting for DHCP". What am I doing wrong?

Thanks in advance.

Autoreply: I've connected the receiver to the Ethernet instead of the Wi-FI and TV shows the IP address.