Found this in another thread about the same issue
Worked for me. Running plex on a windows 7pro box with top of the line components(from 2010)
Basically
1-open your plex web gui and open your livetv dvr settings. It will tell you lies, ignore it.
2-rigth click plex in your system tray and exit plex.
Count to 10. web gui tosses words. they arent important.
3-go to plex in your apps and start it.
4-on the web gui you should see your tuner. Delete it. It’s pure evil and talks about you behind your back
4a-(optional)-repeat steps 2 and 3. I did this but i dont know if its required
5.-the web gui should have learned its lesson and be ready to obey now. set up your dvr/livetv stuff with a smile becasue your secrete collection of Buckrodgers episodes will continue to grow.
