Unplug one end of all HDMI cables, unplug any other connection and finally remove the mains power. Let it sit for at least 10 minutes then apply mains power and re-test. That's about it for user resets for what you describe.
After that http://www.lg.com/ae/tvs/lg-42LA6600 has chat and phone numbers for many countries.
i have a smart tv lg 42la6600 when i want to turn it on just the light of the logo turn on and the tv show black screen and restart again
can someone help me plss thank's

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