1. Check the manual for any reset feature.
2. Does it still work with the laptop?
I have a five year old Samsung LCD 39" TV. Once I connected a HP laptop's HDMI out put to the TVs HDMI input. It worked on with the laptop. But now it does not accept any HDMI inputs like Cable box or a DVD player with HDMI. Now I have connected them with RCA cables with reduced quality. How can I get the HDMI input on the TV to work again?