Check whether you can use the buttons on the your TV
The remote control might be low in battery power. Replace if necessary
Clean the sensor lens on the TV and the remote control with a soft sloth
Operating range between TV and the remote control should not be more than approximately twenty feet
Check if the remote control is in the correct mode, TV or DVD. (For LCD TV with built-in DVD player only)
Make sure that the remote control is not in the sunlight
Static electricity build up may cause this. Unplug your TV for a minute and try remote again