So, because of the new agent desaster for music files, I finally need to create a new library for my music collection, because the old one is a total mess and I dont want to edit thousands of files manually, to clean them up.
Plex isnt able to use the correct data from the tags anymore. Even when a field like Artist is completely empty. It stays empty even after I used “update metadata”.
I just made a test and added a new library with one directory of my old library and all the metadata were imported correctly. So thats why I think its best to create a completely fresh library.
The problem I have with creating an new library is, that all song ratings are gone which I manually set for each and every song last year. It took me several months to do that, so I dont want to do that again for the new library.
Any1 knows a way to setup a new library and use the ratings from the old one? Or is there another way to fix my old library?
Because there is no answer to my issue, I will answer it myself.
But first I have to say, that all this new Metadata thing s***s really bad. As I can see, I am not the only one with issues after the “new” Metadata feature, because the forum is full with topics regarding this stuff.
I still cant believe why Plex is forcing me to use this bad folder structure. I organize my files completly different, because I hardly have complete albums with all songs from one artist and I dont want to make thousands of folders just for one song.
It was never an issue with my collection, because I really care about the ID3 data and keep them clean before I add new files.
The solution to my problem was, that I used a backup I made (before the update desaster from Plex) from the database and replaced it. But I first had to change the scanner to “Plex Music Scanner” and the agent to “Personal Media Artist”. With all others, the artist was removed after I refreshed all metadata. I read in another post, that this was intentional. If the album artist is the same as the artist, the field will be erased. Also track title was removed from so many songs and the album artist was set to one that was found firt in the folder I think.
(And yes, I checked that I want to prefer local media data)
All I can say is WOW!
So with alot of work (gladly I just needed to rate about 150 songs again), I got my library back to the state it was.
It stays empty even after I used “update metadata”. 
