It's a common problem, but the fix is long and tedious. You do have to dismantle the keyboard... First open the case -- one screw on the back, lots on the bottom, then with the machine in the normal operating position, lift the top case up, turn it counterclockwise and put it down alongside the machine. The monitor is in the cover -- take great care not to break the CRT neck. Then unplug the edge connector and ground wire (faston tab) from the monitor PCB so you can put the top cover out of the way. Remvove the keyboard bezel (half a dozen screws). 'Friendly' machines have the keyboard ribbon cable plugged into the keyboard PCB -- if so, unplug it there and remove the keyboard. Others have it soldered to the keyboard PCB. With those you have to remove the shielding and a cable clamp over the CPU board at the back, unplug the cable at that end, and feed it under the disk drives. OK, you've got the keyboard out. Pull off all the keycaps, including the reset button (make a diagram of the positions -- graph paper is good for this). Flip the keyboard over, and desolder (!) all the keyswitches, but not the reset button. Make sure all the pins are free. Undo the screws, and lift off the PCB. Unlcip all the keyswitches from the metal frame. Nowtest the keysswitches. Measure the resistance between the pins when the switch is prssed. A 'good' one is a few hundred ohms at most. Sort those out first. Take the 'bad' ones apart (the housing unclips, then there's a spring, plunger, rubber dome with a conductive rubber block inside). Clean the parts, particulalry the contacts inside the base, and the conductive rubber contact. Put them back together and test again. Any that test OK now are classed as 'possibly OK'. If you still have 'bad' ones, take them apart again, and rub a 6B pencil on the conductive rubber contact. That should get them working. But class these as 'marginal' Put the PCB back on the metal frame and screw it in place. Take the 'good' switches and put them in the most-used places on the keyboard. When I did this, I had enough 'good' ones to completely fill the alphanumeric area, leaving 'marginal' ones for the number pad (which is not essential). And then, as I jsut implied, put the 'possibly OK' ones in the slightly less-used parts, and the 'marginal' ones in places you can do without. Solder them all in place (this doesn't take that long!), fit the keycaps, reassemble the machine. -tony