I had the same problem 6 weeks ago on my 2200. Get the instructions from Dell website about installing a new keyboard for your machine model, so you know how to remove the plastic cover (all you need is a regular screwdriver to pop open the back of the top cover (if you will, nothing to actually unscrew), then they explain how you pop up the keypad, and carefully remove the connector, I wiped mine with a dry clean cloth, and put it (my original, not a replacement) back in, popped everything back in place and it has worked like a charm since! Be sure to unplug everything, remove battery, and carefully follow Dell's instructions re. making sure you have no static electricity on you when you do this. The Dell instructions were very precise with pictures showing exactly where to place the screwdriver, how to pop things open etc. I printed off the entire set of instructions, including the introduction about making your own repairs. I cant' remember if the info. I found was in something called an owners manual or what, but I'm sure after a little looking around you can find what I found...I think it was in a .pdf format. Hope this helps....

Larry

PS I have a similar reply a month ago or so to someone else who posted a keyboard question similar to yours (and mine) and you can find what I wrote then under my username, Kreugerl, or just search for "keyboard problem"