- verify the date and time setting of the server machine for correctness
- verify that the Plex icon is actually present in your task tray area (and that it doesn’t vanish when you move the mouse pointer over it)
- You need to reclaim your server, but don't dare to touch the Windows Registry
- for re-claiming the server after step 3), you may need to use the new method – depending on the software version of your server: New Claiming Requirement for Windows