Configurator 2/AppleTV "The device may be activation locked"

[Garacesh]

Reimaging a faulty AppleTV that stopped showing up on the AirPlay menu, it happens every now and again, no big deal, just Restore, reconfigure, job done. But this one's deciding to play funny buggers with me.

If I try to Prepare the device¹, or add a Blueprint², I get the following error:

 

Unable to activate "Apple TV".

The device may be activation locked. Continue on the device or use iTunes to activate it and try again.

[stop] [Try Again]

Edit: It appears that attempting to add a profile is what triggers the error

 

Launching iTunes does absolutely nothing, just displays the U2 album Apple decided everyone had to own a while back. No "Hey there's a device plugged in" etc you usually expect (or that I've come to expect from iPads)

If I plug the AppleTV into a monitor, I can play around in the settings and I don't see any kind of mention of a previous account (whereas for example with iPads it won't let you do anything until it's been unlocked by the old account. I'd expect similar functionality here if it were actually activation locked.)

 

The thing is, these AppleTV's have never had an account associated with them, and they've always been set up via Configurator 2, so they shouldn't be activation locked at all.

Is this some quirk of the latest tvOS? Or has someone mucked about with it and tried to associate an account with it?

 

1: I don't recall if I'm supposed to prepare these or not, it's been a while since I've had to do it, but..

2: I definitely know I always use the Blueprint, so that should work regardless.

Edited March 6, 2018 by Garacesh

[FishCustard]

Try plugging it in to the computer, opening a terminal and running cfgutil restore, which will reinstall iOS (without the faff that Configurator can make you jump through). Then once done try cfgutil activate, or try preparing again.