Warning!: For security, we very strongly recommend that you do not allow any of these “additional” ports through the firewall or to be forwarded in your router, in cases specifically where your Plex Media Server is running on a machine with a public/WAN IP address. TCP: 32469 (access to the Plex DLNA Server).TCP: 8324 (controlling Plex for Roku via Plex Companion).UDP: 5353 (older Bonjour/Avahi network discovery).UDP: 1900 (access to the Plex DLNA Server).The following additional ports are also used within the local network for different services: TCP: 32400 (access to the Plex Media Server).The most important port to make sure your firewall allows is the main TCP port the Plex Media Server uses for communication: This is not discussing ports on a router. I hope that an uninstall and reinstall will somehow magically place the Plex Media Server on the 'white list' and will stop blocking the ports in the Firewall.Note: This article is discussing ports in the local firewall of the computer running Plex Media Server. From looking on this support forum, users are getting their issue resolved, but unfortunately, they are being resolved without documenting HOW the issue was resolved. For the benefit of others that also run Plex Media Servers and also subscribe to AVG 2017 and are experience this same issue, I am going to uninstall and reinstall both AVG Tune Up and AVG Protection. The Plex Media Server running on my Drobo5N is still accessible internally and externally which definitely points to the AVG 2017 update being the culprit. Unless I disable AVG Protection (specifically the Firewall portion), even if PlexMediaServer.exe and PlexMediaServer.dll are added to the Exceptions list, the Plex Media Servers running on both of my PCs are not accessible.

Both of my Plex servers are not accessible externally or internal on my network since the AVG 2017 update took place.

Plex media server port number