It seems that the issues in here about this topic are all solved by “rename your files”. My videos are not TV shows and even artificially giving them S01E01 does not help plex find them when it scans the folder. Here is a screenshot of the files: https://i.imgur.com/CKZMu83.png
Plex finds only the first two videos listed in the Liverpool folder and none of the Celtics Lakers 30 for 30 folder (although it does find the folder, just no videos in there).
Have you verified that these files are valid video files and are playable with a regular player? (e.g. VLC)
Try to put this library into the ‘folder view’ mode.
Yes, it shows the folders correctly. All of the videos are the same file type and codec and I have watched them without plex fine.
I put it in folder view and it shows the folders correctly but there are only the 2 out of 4 in the one folder and it shows the other folder as empty even though it has 3 videos in it.
On most Linux systems, Plex is running under the user account plex.
Which means your files and folders must grant this user at least ‘read’ permissions.
Because when you put files and folder onto your NAS, you are not authenticating as user plex but with a different user account.
I am not an expert on Linux and Netgear NAS’s at all, so I can only refer you to this post here: Plex not seeing TV Shows