Just ignore the DOuble NAt error
Basically it means your router and the modem do teh same thing and thast normal behaviour
Your inter will still work for all device and you will be able to Backup and use the internet at the same time..
if it is in bridge mode you may be tempairally allow to get online but its will not last ands your back up will fial at some point ot nor fully complete
Now thast being said the only device thast support wireless back up iis the time capsuale...
The exterme can have adn external HD conencted to it but its has to be formated as ewither fat 32 or mac os x extende journaled is onlt use for data storege not for a back up drive
However, I want to use Back to My Mac option to access this hard drive from across the world when I travel. I am not worried about backing up to time machine as I dont really do it.
I only want to share my hard drive over the internet. But whatever I did is wrong as the Back to my Mac option is not coming up in finder. I checked in finder pref and it is fine as well.
Done. It says, "Set up router for better performance", Adding,"Back to my Mac is slow because NAT or UnPnP is not enabled, set it up in the router"
Now,I go down to my Wimax router but I dont have any option for turning these on.
So,when I go an enable it in the Airport Extreme, it says another device is enabled with NAT.
In the iCloud pref, it talks about the same error. 'Back to Mac' still not displayed in finder.
so i looked into the NAt and UnPnP
the apple router automictally allw thast to go through as apple make all the router leave all apple need port to allow homesharing/airplay/back to my mack to work.
Conact the mian router manufacture and see about perhaps turnign the wireless function off to remove the Double NAT and to Veriufiy it can support UnPnP