You updated from DSM 6 to DSM 7, correct?
Are the database files still present in
/Plex/Library/Application Support/Plex Media Server/Plug-in Support/Databases?
If no, stop and reply back to this thread.
If yes, then your old server is still present in the /Plex shared folder.
You need to uninstall, then re-install PMS.
First, uninstall Plex Media Server. Choose Erase all of Plex Media Server from this system. This will remove the Plex Media Server using the /PlexMediaServer shared folder. It will not touch the files in /Plex or your media files.
With File Station, make sure /PlexMediaServer is completely empty.
Now re-install Plex Media Server following FAQ 27 - Migrating an existing PMS from DSM 6 to DSM 7.
When setting user PlexMediaServer permissions to /Plex, be sure to check the box to “Apply to this folder, subfolders, and files.”
The install process will migrate the data from /Plex to /PlexMediaServer.
If successful, /Plex will be empty except for a migration.log file.
Use Plex Web to access the server via its IP address, http://syno_ip_address:32400/web. You should be able to login, claim the server, and access server settings, your library, etc.
