So not being able to connect the app to the network was annoying, to say the least. Once the Plex app would open and stay that way, I wanted to get up and running as quickly as possible. Plex Samsung smart TV app will not connect to the Plex Media Server It takes a few minutes to reset and reboot but once done, the Plex app worked perfectly.

Navigate to Settings, Support, Self Diagnosis, and Reset.I had to perform a factory reset on my TV in order to get this to work. Yet every time I opened it, the app opened to the plash screen and then closed again. The app installed without a problem and appeared in the apps list. I had a good WiFi connection to the network the Plex Media Server is on and everything looked good. I had performed a firmware update on the TV to get the latest version of the Samsung Smart Hub. This problem took the longest to figure out. Plex app opening and closing on a Samsung smart TV Both of which I was able to figure out with a little help from the web. The second, the app would open but not connect to the Plex Media Server. First, the app would open and then immediately close. I had a couple of problems with my setup that took a couple of hours to figure out. Troubleshooting Plex on a Samsung smart TV

My plex server