PMS shut down every time I want to launch it

[ChuckPa]

That tells me a great deal. It sounds like someone played with / broke the shared folder permissions.

We can fix this:

1. Stop Plex
2. Rename PlexMediaServer shared folder → PlexMediaServer.new
3. Rename PlexMediaServer.OLD → PlexMediaServer
4. Follow the procedure below to fix all the permissions inside the PlexMediaServer shared folder.
5. Attempt to start Plex.
6. If it works correctly, We will be back to normal.

Please let me know your progress.

Synology FAQ - Questions, Answers, and How-To's

FAQ 32: Repairing the PlexMediaServer shared folder While DSM 7 manages the permission of the PlexMediaServer shared folder itself, it does not manage the permission of files placed inside. This means any modification of permissions can cause PMS to fail. Frequent causes: Placing media in the shared folder – Which should NEVER be done. This is for PMS internal (metadata) use only. Special allowed case of adding plug-ins but must be installed correctly. One of the biggest confusion po…