After much frustration, I have found a solution, at least for me.
Downgrading is not necessary.
IOS 11 for Apple TV will not read AAC encoded MP4 files anymore. I re-encoded all my movies as AC3 mpeg-4 files and they all play flawlessly. When people create videos from their DVD's, almost every encoder uses AAC MP4 as the default setting. Some people only have iTunes movies, and they should all work fine. This is why some people were having problems and others were not.
Just recode all your movies to AC3 MPEG-4 and you should be fine.
Hope this helps.
Downgrading is not necessary.
IOS 11 for Apple TV will not read AAC encoded MP4 files anymore. I re-encoded all my movies as AC3 mpeg-4 files and they all play flawlessly. When people create videos from their DVD's, almost every encoder uses AAC MP4 as the default setting. Some people only have iTunes movies, and they should all work fine. This is why some people were having problems and others were not.
Just recode all your movies to AC3 MPEG-4 and you should be fine.
Hope this helps.