a lot of times you will get that message if there is no internet access. Might want to try a power cycle of your router and modem to see if helps. Sometimes you have to do this even if your other devices have internet access.
http://www.pctechbytes.com/networking/how-to-power-cycle-a-router-and-modem/
My 2 week old samsung 4k tv suddenly will not play any apps on smart hub. It states not available. Numerous calls to samsung and many resets, updates and endless holding have not resolved the problem. I am very upset at the response from samsung. Any one else have this problem? Model # UN40HU6950 Gene

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