I have had a UA55ES7500 LED TV for a few weeks.
Few days ago, its wi-fi has totally stopped working. Wireless network discovery is not even working. It tries to search for wireless networks and it just gives up. It doesn't even show any list of available wi-fi networks.
And, there's indeed plenty of wi-fi networks (incl. mine) around that I can find with my other wi-fi devices.
Tried shutting down (power off) everything (modem, router, TV) and switch back on but still no luck.
Now connected via wired network as a temp measure.
Initially, had it all set up and running with wireless. Had updated to the latest firmware quite some time back. Just checked that it's still got the latest firmware update.

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