Update manually.
All you need to do is:
- Stop/quit/end Plex Server with the tray icon
- deinstall Plex Server with the regular ‘Apps’ control panel of Windows (do not use 3rd party ‘Uninstaller’ software like Revo etc.)
- for safety, reboot Windows
- download the installation exe of the newer version and install it
(If you want to install an older version of PMS, take a look into %LOCALAPPDATA%\Plex Media Server\Updates)
