Just purchased the un50ru7100f and so far every time I turn off the tv, it does not reconnect to wifi when turned on. I'm finding that only disconnecting power to the tv then back on allows me to reconfigure the wifi. No update available through the tv.. should I return it?
I contacted Samsung on this issue and the fix was to turn "instant on" feature off. I explained to the tech and their supervisor this is not acceptable for a "fix" but it does resolve the issue. The changing of the DNS server which they also suggested is comical since the network adapter is failing to resume when the instant on feature is enabled. Now I have to decide if I'm going to return the tv or wait for Samsung to release a new firmware that might fix the issue and give me the instant on feature again.
Have you tried the troubleshooting here? http://www.samsung.com/us/support/troubleshooting/TSG01111014
One suggestion is to make a Hotspot on your phone and see if the TV is able to see that network.