Just when I thought all the issues were fixed, up pops another one. Using Norton 360 8.6.4 Build 54 and Big Sur 11.4 and all other Apple devices have latest OS version. I have Home Sharing turned on, on all my devices using my iCloud account. Movies and videos downloaded on my iMac from the Apple App Store and in the Apple TV App Library are viewable and playable on either the Apple TV 4K or the Apple TV App on any of my Apple Devices. However, I recently imported two MP4 videos into my iMac Apple TV App's Library, and they show and play fine there, but do not show or play on any other of my devices.
Per a thread in the Mac Rumors Forum, I tried turning off Norton Vulnerability Protection (the culprit in most if not all Big Sur issues) and, sure enough, works fine, then. Turned Vulnerability Protection back on, and is broken.
Norton Support--you guys have another problem to fix...
Thanks!