Weird music playback problem

[Teunis]

Two years ago I ripped some CD's to .ogg.
Now I found out playing a single file will ask for a for me unknown password.
But throwing (dragging) the file on a player like SMPlayer or VLC will play it.
What could cause this?

[die.boer]

What is probably happening is that the file manager or the application associated with .ogg files is asking for authentication, rather than the file asking for a password.

A few possibilities:
-The file is on a location requiring authentication — for example, a mounted/network location or a folder with unusual permissions.
-The default .ogg application is sandboxed (Flatpak/Snap) and is requesting permission to access the file.
-The default application has a privilege/authentication problem and is incorrectly triggering a password prompt.
-The .ogg files may have been created with unusual permissions/ownership two years ago.
-Less likely, the files are inside an encrypted/password-protected archive or filesystem, although VLC being able to open them directly would make this less likely.

in a terminal run the following and post the output please:

ls -l "/path/to/file.ogg"

file "/path/to/file.ogg"

xdg-mime query default audio/ogg

can you also perhaps post a screenshot of the password prompt ?