I just spent more than hour trying to figure out why iTunes on my computer wouldn't show my music when I tried to sync my phone. Finally figured out that I had to turn off library sync from Apple Music. When I turned it off and plugged my phone back in, the option to sync my music was back. Does anyone know why that happens? Why does "Sync Library" bar you from syncing music from your computer to your phone?
When you enable Sync Library AKA iCloud Music Library in both your computer and your device then they can sync with each other wirelessly and local syncing becomes redundant. All of your qualifying songs and playlists are available everywhere, and those that are not physically stored on the computer or device can be streamed or downloaded on demand. Local syncing can only transfer locally stored files, and cannot transfer DRM protected Apple Music content.
tt2
When you enable Sync Library AKA iCloud Music Library in both your computer and your device then they can sync with each other wirelessly and local syncing becomes redundant. All of your qualifying songs and playlists are available everywhere, and those that are not physically stored on the computer or device can be streamed or downloaded on demand. Local syncing can only transfer locally stored files, and cannot transfer DRM protected Apple Music content.
tt2
Why can't you sync music on itunes while syncing your library with Apple Music?
