You won’t be able to use the old server’s identity, so you need to create a new one. This then means, you will have to tell each and every Plex client to use the new server:
https://support.plex.tv/articles/customizing-the-mobile-apps-2/#reset
https://support.plex.tv/articles/customizing-the-apps/#reset
https://support.plex.tv/articles/customizing-plex-web/#resethome
Excellent. I recommend setting up the new server instance first.
Claim it into your plex.tv account: New Claiming Requirement for Windows
and set up one test library which you can point to a very small collection of video files. This is just to test principal function and transcoder working etc.
Once you have confirmed that everthing is working, you can either
- restore the plex data folder backup, thus overwriting the newly created plex data folder (do this while the server has been shut down!)
- add the registry key to tell Plex server the location of the backed-up plex data.: [HowTo] An extended guide on how to move the Plex data folder on Windows
If the backup of the plex data folder has been made while the server was still running, the primary database file is quite likely damaged. Restore one of the internal backups of this database file: https://support.plex.tv/articles/202485658-restore-a-database-backed-up-via-scheduled-tasks/
