Samsung's services seem to buckle. As this has happened with regularity my advice changed from troubleshooting to "call it in" or "return it for another model."
Bob
Hi, I bought UE48H8000SL a week ago and everything was fine until yesterday. When I try to open the youtube app the screen goes black for a second then returns me to the previous screen. I tried opening it in the tv browser and got a server error. I have no problem opening it from my PC.

Chowhound
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