After a powerful lightning strike nearby, tv signal went off. Did troubleshooting, system restart, problem not solve. Internet working ...
First of all; have you tried using your television for over the air signals using the antenna?
If this works the television should be okay.
If no antenna; does the television work when using a Blu-ray player, or a gaming device?
Tv okay if they work. Then I would get the cable-box replaced at the nearest service center.