My brother made a new plex account, i invited him to my server, it went through no problem. When he logs in (he has spectrum cable) with the new account (yes it is the new account), my server does not show up. We have shut off the tv and relogged in numerous times no avail, and yet when he looks up friends I am there, as are MY friends. Typically in the past my server would be listed after he clicked on “more”.
Also everytime he logs out manually, he has to re-set up his tv with a code rather then simply logging in.
It’s possible that you simply added him as a friend to your online Plex account (Plex’s new “social” features), rather than giving access to your server libraries.
Go to Settings > Manage Library Access to see if your friend’s account shows up on this list, and whether they have Library Access.
