I’ve had this issue for some time. The last working version for me was 1.13.2.5154.
It wasn’t until I found this in the logs that I realized I needed to add the "" to the LocalAppDataPath (“C:” → “C:\”):
Warning: ex: boost::filesystem::last_write_time: The system cannot find the file specified: “C:Plex Media Server\Plug-ins”, couldn’t check file: “C:Plex Media Server\Plug-ins”