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.
Best Answer
Assuming you have ruled out software problems (e.g. by booting to a Linux LiveCD or similar), this seems like a manufacturing defect with the keyboard (assuming your cat hasn't tried to eat it, you haven't spilled orange juice or acid on it, or a different situation doesn't apply that would directly cause failure).
EDIT: It may be worth trying to re-seat the ribbon cable underneath the keyboard. This is roughly equivalent to removing and replacing it; read on.
If it is under warranty I would recommend contacting Lenovo and applying the normal phone techniques to get it replaced promptly. If not, a replacement keyboard is usually inexpensive online and is easy to install with the help of a screwdriver and the maintenance manual (FRU 1100 on pages 47, 48).