I've had a difficult time connecting to the network. I continued trying and it worked fine. I won't try to connect it while my computer is on the net. I get an error two computers are using the same IP address response when I did. I couldn't get them to run together even after troubleshooting.
Do you have it set to DHCP? If your router is working properly, you should have no problem using more than one device.
On the Denon, if you click on Menu, Manual Setup, Network Setup, Network Information- you should see:
Friendly Name DENON:[AVR-XXXX)
DHCP ON
IP Address xxx.xxx.xxx.xxx
MAC address xxxxxxxxxxxx
If you see no MAC address, the network card is bad.
If you see a MAC address and it still won't connect, go to Network Setup and click on Network Connecting. You'll see:
DHCP ON (or OFF)
IP Address 192.168 0 1
Exit
Detail
Click on Detail, then on DHCP- it will assign an IP address at this time. If you don't see an arrow at both ends of 'Network Connecting', exit Menu and try again.
If you didn't do a hard reset and firmware update immediately after the first power up, do that as soon as you get it connected to the network.
You can also do a network reset. I don't remember exactly, but IIRC, you turn the receiver off using the Master Power button and then, press Master Power while holding the UP/DOWN buttons simultaneously. Once the display lights up and flashes a few times, you can release the UP/DOWN buttons before going into setup again.