Thanks for the log files.
Good news is the database migrations completed and there are no signs of database corruption.
However, it looks like the server is now unclaimed (no longer linked to your account). It also looked like the NAS had trouble communicating with hosts at plex.tv.
First, double check the network settings on the NAS. Make sure the IP address, mask, and default gateway are correct. Synology Control Panel → Network → Network Interface tab.
Second, synchronize the NAS with a public NTP server. Synology Control Panel → Regional Options. The NAS time needs to be close to real time for claiming to succeed (not down to the second, but it can’t be hours off either).
Third, Follow FAQ 31: Reset / Reclaim PMS on DSM 7 (Not Authorized - Locked Out) to reclaim the server. You’ll uninstall PMS, then re-install the same version (1.41.6.9685), using the Plex Claim Token method. This is only the application. The PlexMediaServer folder and media files are not touched.
If successful, you’ll see a “successfully claimed by” message.
Then try and login directly to Plex using the NAS IP address, http://ip_address:32400/web. Hopefully you can login, reach server settings, see your libraries, etc.
If the claiming fails note any error messages on-screen and pull a new set of log files.
FYI, I saw all the MediaProviderManager error messages. Not sure what is causing those. It could be that the server is unclaimed and/or having problems communicating with plex.tv.
