I cannot restore the new Software in iTunes

Legacy 2nd gen Apple TV
1

All versions are the latest. When the iTunes script runs I get “The Apple TV” could not be restored. An unknown error occurred (21).

Any suggestions?

2

Trying to a factory reinstall before you JB. Plug your AppleTV in via USB and open iTunes. Let it install the standard software, then unplug it, start SeasonPass and go through the normal JB steps.