I installed the Plex media server on a dedicated Windows 7 machine, and proceeded to try adding channels. I tried on the server side and I tried on the client side (the Roku).
But no matter which way I added channels, they only showed up on the server. I found out they were being blocked.
I solved it by opening port 32400 in the Windows firewall. To do this:
- Go into Windows Firewall
- Advanced settings
- Click on inbound settings
- Click on new rule
- Select port
- Under "Specific local ports" add 32400