Plex server unreachable

My setup:
Server: linux mint 17.3 pms ver 9.16.4 (accessible from Internet connected devices)
Client: linux mint 17.3 local network only access
Prior to ver 9.13 I was able to access the webgui from the client, but now I'm unable to do so, whether it is http or https://[server ip]:32400/web (I even added the /index.html) I keep getting plex server unreachable.