EMP 830 Menu does not function

I have an c. Recently I switched it on after three months. When connected to a DVD player it projects well, but the menu wont function at all. Which eve button I press, the menu main page appears on the screen, but the cursor does not move at all. Once the menu main page comes, and if I press any other button, the menu page goes off. As a result I cant do the focus, I cant tele, do wide, do wall adjustment etc. I have to physically shift the screen or the projector so that the image fits the screen.

please advice ...

ramchandra