I used to be able to watch and use AirPlay to my Samsung but a few months back I started receiving multiple error codes. The latest two are N/63C5B358 and 645BD68B.
I completed the recommended steps (multiple times), making sure I'm up-to-date for each of the devices and logging into Manage Your ID on my MacBook without difficulty. I removed and re-added the AppleTV app on my television as well.
Nothing works.
While I can still watch movies and such from my Mac, I'd much rather do so on my larger television screen. I have not found a solution and it sounds like a whole lot of people are having the same problem.