I have just tried to install plex and tried all the above solutions and still my Plex light stays red.
systemctl status plexmediaserver.service -l
● plexmediaserver.service - Plex Media Server for Linux
Loaded: loaded (/etc/systemd/system/plexmediaserver.service; enabled)
Active: failed (Result: start-limit) since Wed 2016-12-21 16:01:54 GMT; 4min 33s ago
Process: 25056 ExecStart=/bin/sh -c LD_LIBRARY_PATH=/usr/lib/plexmediaserver / usr/lib/plexmediaserver/Plex\ Media\ Server (code=killed, signal=ABRT)
Process: 25051 ExecStartPre=/bin/sh -c /usr/bin/test -d “${PLEX_MEDIA_SERVER_A PPLICATION_SUPPORT_DIR}” || /bin/mkdir -p “${PLEX_MEDIA_SERVER_APPLICATION_SUPPO RT_DIR}” (code=exited, status=0/SUCCESS)
Main PID: 25056 (code=killed, signal=ABRT)
Dec 21 16:01:49 supply.tk systemd[1]: Unit plexmediaserver.service ent ered failed state.
Dec 21 16:01:54 supply.tk systemd[1]: plexmediaserver.service holdoff time over, scheduling restart.
Dec 21 16:01:54 supply.tk systemd[1]: Stopping Plex Media Server for L inux…
Dec 21 16:01:54 supply.tk systemd[1]: Starting Plex Media Server for L inux…
Dec 21 16:01:54 supply.tk systemd[1]: plexmediaserver.service start re quest repeated too quickly, refusing to start.
Dec 21 16:01:54 supply.tk systemd[1]: Failed to start Plex Media Serve r for Linux.
Dec 21 16:01:54 supply.tk systemd[1]: Unit plexmediaserver.service ent ered failed state.