Fotos, Catalina 10.15.2, Error 1000

Hi all,

I upgraded on my MBP Late 2016 to Catalina 10.15.2. I have a fotos library with approx 20.000 pictures and movies from a trip around the world. Very important and crucial to me. It is on an external Samsung T5 1TB SSD disk. The drive is formatted with APFS and I dont use iCloud Fotos. The library is approx 15GB and the pics are not imported, but on the same drive.

When I connect the drive I have to enter a password. Encrypted drive.

Ignore Owners on the drive is enabled.

my own user has read and write rights.

When I double click the fotos library, it tells me that I open it the first time and if I really want that. Open.

Library will be updated.

Library rights have to be repaired.

The library is protected or I dont have the rights to change things. Weird, I use it with my user and if I go to the terminal it shows me:

drwxr-xr-x@ 7 kay staff 224 Dec 27 15:59 Weltreise.photoslibrary

I am the user kay (who is also admin), so I should have all rights.

I checked the rights on the directory

drwxr-x--- 24 kay staff 768 Nov 12 19:01 .

To me this means I have all rights.

I click on repair and it asks me for my password.

I get a message that the library could not be opened, Error 1000.

What is wrong?