I try this (from Damian Smith1) and it worked
Did you try theses instruction from another thread. Everyone who had success appears to have use OPEN DNS.
go to the ATV settings => General => Network => Configure TCP/IP => Manually=> Skip the IP address going directly to DONE = > Skip the Subnet Mask going directly to DONE =>Skip the Router Address going directly to DONE=> Now change the DNS Address to 208.067.222.222 ( before changing the setting write the number down so you can change it back once you finish) and hit done. Once you get the "Configuration Succeeded Message hit DONE and go back to Update Software. It will take a like 20 seconds to start downloading. Once the upgrade is completed follow the same instructions to go back and change the DNS Address to the original number.
Otherwise I'm stumped. you should submit a bug report to Apple via the Apple feedback webpae.