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same here, like this for a couple of weeks. I have restarted and reset several times. It won't allow me restore. I have rebooted my router too. No problems with any other devices connected to my wifi!
just another increasingly useless Apple device - "it just works" really???
recently bought an iPhone 6s, spent hours with a clueless genius and then a day and a half with senior tech staff by phone trying to restore from both iCloud and hard drive backups without success...
I find that the fault lies in the cable from the Apple TV to the power socket
Try moving and straightening this cable
when your apple tv reconnects with wifi try not to move this cable
In my personal experience with Apple products their cables are very inferior
I've had to replace iPad and iPhone recharging cables
Come on Apple do something about this