Fawaz Faizal, from what you are telling us, I would replace the keyboard. It sounds like it makes intermittent contacts, possibly due to a short-circuit is some of the traces. there is of course also a possibility that it is your keyboard cable, or the connector. Worst case scenario would be a bad keyboard processor. Replace the keyboard, they are available at multiple places and are not that expensive. You might want to Google for a supplier to your geographical area. [http://www.youtube.com/watch?v=jHSqcQrOQ6s|Here is] a video showing you the replacement and [http://www.hp.com/ctg/Manual/c01301275.pdf|here is] the service manual. Hope this helps, good luck.