Would you mind sharing some more details?
e.g. – how is playback failing… do you get some error message? Is this about media from your local server, a shared library or some of the online media sources?
The logs say Plex fails to access the file (“operation not permitted”).
Have you configured your Mac to allow Plex to access media on that drive? → System Settings > Security > Data Protection; there should be a “Files and Folders” section where you can specify what types of volumes certain apps can access.
The access was already granted. I removed it, rebooted, granted the access back, but it is still not working at all. Same error message.
It’s just a mess… I don’t understand how it has happened. The only thing I can point out is the last iOS update. If it was because of this update, I wouldn’t be the only one experiencing this…
Can you double-check if macOS the path to your media is still the same?
e.g. comparing > Info of a movie to the exact path as you see it in Finder. Sometimes macOS will recognize while it thinks it’s still connected and therefore adds e.g. a number to the volume name (e.g. Phil's 4 To-2 instead of Phil's 4 To). From the perspective of any app that’s looking for a particular file path, that file will no longer exist.
Another thought… can you still access the media from that drive through other apps (just trying to rule out the drive has a deeper issue)?
Regarding the macOS data protection settings…
What kind of drive is that volume located on (e.g. internal, external, network)? Does the Plex Media Server entry have access to all applicable types?
I’m using an external hard drive. I just double and even triple check and Plex Media Server has access to all applicable types.
I tried with a USB memory card and it works. So there must be something not working between Plex and my external Drive (that is working very well with anything else).
Ok, what OS version are you using? Monterey. If so I read a few sad story of issues updating to Monterey. It is still possible to downgrade to Big Sur as last resort.
Try the following as often it can be fixed by doing these.
I think therrien22’s comment was a typo/mixup. its related to the OSx not iOS update. (IE the mac OS, not the mobile OS, both are made by apple and have very similar abbreviations)