My 2011 Samsung Smart TV (model UN55D7000) stopped loading apps due to lack of internet connection even though when I went to network settings, it showed internet as being connected. When I went to the Samsung website they had an alert about this problem, so I thought I would share:
http://www.samsung.com/us/support/video/tvs
Here is what they recommended (there are embedded links with directions, which you have to go to link above to access):
"If you are experiencing any issues with Smart Hub not loading or certain apps not loading, try these steps below:
1. Disconnect your TVs power cord from the power outlet.
2. Wait 5 minutes and then reconnect the power cord, and then try accessing Smart Hub and apps again. If this does not resolve the issue, proceed with step 3.
3. Change the DNS server on your TV. If this does not resolve your issue, proceed with step 4.
4. Reset Smart Hub. (2014 or earlier, 2015). If this does not resolve your issue, proceed with step 5.
5. Change the country code on your TV to the first available country. After saving, change the country code back to the United States. (2014 or earlier, 2015). If this does not resolve your issue, please contact us."
I was able to do 1-4, which did not help, so I had to chat with samsung, who (content edited)
(NOTE from moderator: Any post with service menu advice was removed as it can brick a TV. Please don't post service menu advice. Let Samsung do this or guide folk to avoid folk coming after you if the TV fails.)
But what a silly thing to have to do to make your TV work. Still not impressed with Samsung after 4 years of owning this TV.

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