I’m running PMS 0.9.16.4 on Windows 10. In general it has been rock solid, except for remote access. The machine has a static IPv4 address and the router its behind is configured to send all traffic to this machine. Other servers (SabNZBD, IIS, CouchPotato, uTorrent web UI) are accessible from the outside just fine. I have had PMS work fine in the past as well, but it seems to fail inconsistently.
Currently it’s saying “Your server is signed in to Plex, but is not reachable from outside your network.” I have restarted the server, signed out and in, and restarted the whole machine.
I don’t think so… the router is an Airport Extreme, other servers on the same machine work fine, and PMS has worked fine in the past. I’m wondering if there’s something I should be hunting for in a log file that might provide a clue.
I would say check a few things:
Port forwarding: Using default settings in Plex, forward 32400 to the appropriate internal IP. Make sure both the external and internal ports are correct (again, by default, both should be 32400).
Firewall: I think it is done automatically by Plex, but allow Plex DLNA Server, Plex Media Server, and Plex Scripting Host on both public and private networks.
You make it sound like these things have already been checked, but it doesn’t hurt to double-check.
I have had the occasion where I needed to use a customer port, for some reason…give that a try. Manually select the port 32401 or something, make the necessary port forwarding changes, and see if that works. Likewise, try making sure that the “manually specify port” box is unchecked when trying the default port.
Wow, a few replies made it in while I was posting my comment 
Firewall settings indicate that the Plex DLNA Server, Media Server, and Scripting host rules are all enabled and set to “allow”.
On the router, I have a “default host” set to the internal IP of the machine, which sends all traffic to it. I do not have any manual port forwarding rules set, but other servers, and things like Remote Desktop, are working fine.
No different in behavior with the port changed to 32401.
Restarting the router fixed it, though. I seemed to have just forgotten that every time I install a new version of PMS, I have to restart the router to get external access to work again. Not sure why…
