"hi - For anyone searching for an answer to this question - I just had the same problem and called apple support as instructed. They are arranging for the Apple TV to be collected and returned for repair.
I asked if there was any way to restore myself and was told no. I said that I was concerned that if, for whatever reason, I needed to restore the Apple TV after it was out of warranty that it would cost me - they said that if it was due to a software update problem then there would be no charge - even out of warranty.
I'm amazed that there is no way an owner can restore the box to factory settings - this seems like a really bad idea."
"This happened to me yesterday, was watching a movie when the video froze and a few seconds later the TV rebooted. Was greeted with the exclamation symbol and a URL support.apple.com/appletv/restore. I tried the power cycling trick but that didn’t work. So booked a session at the Apple Store.
The tech at the genius bar had some useful info. He said the restoration method now uses the Ethernet port. He confirmed the bootloader will try to redownload the OS via the Ethernet port. However he didn’t clarify if this was downloaded from the Internet or from the Apple Store’s LAN servers.
He plugged a Cat6 cable into the GigE port, unplugged the power cord, counted to 15, then plugged the power back in while holding Menu + Home on the remote at the same time.
Unfortunately that didn’t work either so he handed me a new ATV 4K. Luckily mine was still under warranty. But if anybody else has this happen out of warranty give the Ethernet method a try."
"Only thing that worked for me was repeatedly plugging it in and then unplugging it. I would leave it plugged in until the service screen would appear, then I would unplug it. Repeated 5-6x and finally it just booted up normally, though it seems with all caches wiped (e.g. it had all the apps, but no content/images loaded).
Also have seen some people say after 5-6x reboots it may bring up a diagnostic screen where you can restore the device to factory.
I think Apple doesn't post this as an official solution because its so ""inelegant."" But it makes sense to have multiple restore options with the USB port removed!"
"I was reading some other articles. If you installed XCode, there is supposedly an option to link the Apple TV with Xcode 9, either wirelessly or via the Ethernet port.
