Try naming the input "----" something else, and then try naming the input "PC" to see if the computer is able to reconnect. Renaming the input may reset the input.
i have a Asus g50-vt laptop and a LCD 32" LN32A330 720P Tv, for several months ive used my tv to watch movies and play games using a HDMI cable between my laptop and my TV, recently i disconnected the HDMI cable from the laptop after i was done while the tv was still in the HDMI mode ( which i dont recommend) and my laptop screen went totally gray, i got worried for a while but i just reinstalled my drivers and everything was in color again, the best lesson to avoid this is to always swith the TV off or, just take it out of HDMI mode when you want to unplugg it, after this episode i tried to connect once again my laptop to the TV to watch a movie and, while my laptop did recognize the TV ( Nvidia control panel recognized both screens) the TV always says theres no signal. I thought the problem was my drivers or my cable, or just that i had to format my computer, but that all was discarded when i coneccected my laptop to another TV ( samsung 32" series 5 1080P) and it worked perfectly fine, i was wondering what could i do to solve this problem in my other tv, which im very concerned off. i appreciate the feedback