You can do this via a hidden setting in the Windows Registry
https://support.plex.tv/articles/201105343-advanced-hidden-server-settings/
Edit: 1st link is listed in the tips & tricks section; 2nd link is an official support article
You can do this via a hidden setting in the Windows Registry
https://support.plex.tv/articles/201105343-advanced-hidden-server-settings/
Edit: 1st link is listed in the tips & tricks section; 2nd link is an official support article