I am using Lenovo IdeaPad Z560. The keys 1, 2, 3, 4, 7, 8, 9, 0, F10, F11, F12 are not working. The ones below the function keys, that is. I used numpad to type this question. What could be the possible reason? How do I solve this? This is going to be a big problem. Please help.
Edit: In the following image, I have marked the non-functioning keys with red rectangles.