Hi all,
I got recently the Denon CEOL N7 and unfortunately there are a few flaws.
A big problem with this device is the fact, it uses the same MAC-Address for LAN connection and WLAN connection. This causes a huge variety of problems, because no router expects this and may crash or behave unpredictable.
Please be aware of this and either connect it via LAN (and prevent seeing the device via WLAN) or just use WLAN and never connect to LAN.
Unfortunately the update process is very unstable and likely to fail and even more over WLAN. I my case the update failed several times over network leave the system in a state no network connections could be done. So the last chance was a CD update as described earlier in this thread.
I was lucky to figure out some faults and workarounds and successfully updated via CD method.
After that I got a further update via Network which this time succeeded as well and now the stereo is up to date and fully working. Even AirPlay update is now included without extra costs (But needs of course extra installing).

Here are some essential tips:
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- Burn the CD in all standards including UDF!
Denon described to create the CD in ISO 9660 standard only. This is actually wrong!!!!
I was lucky to see the filenames differ on the CD and the content of the ZIP file, because the names have been shorted to 8 characters.
Unfortunately it do not like Joilet standard but a CD supporting all standards ISO 9660, Joilet and UDF(!) solved the problem. After I change my CD burner to this setting the stereo tooks the firmware files and loaded it successfully.
- Reboot your network router and recheck routing information about the Denon CEOL
After the firmware update succeeded I was not able to connect to WLAN, because my router (FritzBox) remembers the MAC address to be on LAN. Even a restart of the router didn't solve it. I have to reconfigure my router to forget the entry for Denon CEOL. After that a connection was possible. This goes so far it didn't even see the SSID and leave me think WLAN is broken at all. But the problem here was actually the router.
All people reporting network issues, please double check your router. As described in the beginning using the same MAC address twice causes many (may be even all) routers to fail.