My ATV keeps dropping home sharing. I tried to reset it and it keeps saying unable to download updates at this time. it's been a few weeks of the same message.
That would indicate a network issue.
If on wifi try ethernet.
Make sure router is up to date. Reboot ATV and router.
Go to istumbler (Mac) or netstumbler (PC) to get a report of the network. Look for signal strength and noise.
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