to what result did you get with that troubleshooting?
- does your router support UPnP?
this is required to allow Plex to automatically make itself visible from outside your home network- if it doesn’t… have you already tried the same by assigning a manual port forward in the router (and configuring Plex accordingly)?
- can you access the public IP of your router at the defined port from outside your home network?
- with UPnP: using the port tcp/32400
- with a manual port forward: using the tcp port you configured in the port forward
I’ve run the error message through Google translate.
It appears, Plex considers it might be in a “Double NAT” situation. That means there could be multiple routers, gateways or access points that establish their own network. In such a scenario Plex might be able to make itself available to “the outside” – but “the outside” turns out still to be inside your home.
This can happen if you have a modem from your internet provider and a different router of your own – with both devices being configured to create their own network… this is most visible by them having their own DHCP. In such a setup, you should make sure that one of the devices is configured in “Bridge Mode” (making it extend the network established by the superseding unit).
Occasionally this can happen if your ISP is not assigning you a public IP address but manages their backbone like a home network (CG-NAT). If that’s the case you’ll need to ask your ISP if they can make an exception for you – or there won’t be a remote access for you.
