My bet is Samsung is tinkering with their services.
Call it in. Do not change your network or reset.
Starting Yesterday at 7 pm all my apps are gone.
I don.t understand how this happened, nobody touched the Smart Hub or other setting in about a week i only watched a few channels for about 2 hours everyday but nothing more because i was tired after work.
This is a image with my current smart hub screen.
http://s3.postimg.org/4aix7za4f/20151012_231701.jpg
I tried reseting the Smart Hub, i tried resetting the TV and Hard reset nothin worked.
Please Help.

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