Genius Error when Syncing Apple Music on Mac

Alright. This did the trick for me.

1. Locate your music library folder and back it up

2. Reset your library: Start Music app holding down Option. Choose Create a New Library

3. Locate the new library folder in Finder. Move your old music files to the the folder Automatically Add to Music

4. Wait until your library has synced into the Music app

5. You may have duplicate songs in your library after the procedure. I spent a couple of hours deleting all the duplicates manually. (If anyone has a better option for this, let us know!) You find the duplicate files by Option-clicking Archieve > Library > Show Exact Duplicate Items.

Well, after upgrading my MacBook I faced the same issue and - at least for myself - were able to solve it. I use Apple Music using my .me Account A, but from very old times I also have songs in my playlist purchased once using another Account B. It seems Apple Music has some problems with it.

I moved all with Account B purchased music files into a separate file folder and removed the entries from my Music Playlist - restarted Music and now Music is synching my Cloud Music Library.

Maybe that helps one or another ....

Yeah, so after being on call for approx 2 hours with Apple today this is apparently a rare error. Check you've not got any VPNs on your Mac as apparently it can interfere. I still don't have any fix for it but I have another call with them tomorrow.

I had to reinstall macOS which yielded no results. AM works on every other device I have just not on my user profile. Good luck with this error 🥲

You can check the location of your music library folder in the Music app preferences. Just make a copy of that folder. (This is just a precaution. You might be able to move your old music to your new library even without copying your library first.)

I'm not sure about the play count data, since I don't follow them actively. At least most of my new music library songs seem to have kept their play count data after the transfer, but I cannot guarantee they all have.

I transferred my library a week ago, and I haven't seen the Genius error 4099 since. Sync has been also working perfectly.

I’ve wasted nearly an entire day on the phone with Apple Support for several hours (3 separate calls). The frustration is, I only called in because I had several duplicate playlists on my iPhone, the rep had me toggle off Sync Library, and that caused me to lose all my playlists. Now, no one can fix it. I’ve had Apple Music/iTunes for over 15 yrs, so tons of curated playlist.

I've been on chat with Apple for the past hour with the same issue, I've had to be referred to a senior advisor on call tomorrow to see what the issue is 😳

i've also got this issue!! please please let me know if you find a solution.

Any updates on this issue? I just encountered it today too.

worked for me. thank you!!

How exactly does one backup their library?

and do you lose play count data doing this?

FINALLY! This works! I've been looking for over a week and finally found this.