Mark, you might also check to see which thread, the one in the cabinet or the one in the screw, is the problem. Use a wire brush to clean the screw threads and see if you still have a problem. My guess is that you got paint in the threads in the cabinet. If this appears to be the case, "chase" the threads with a 3/16-28 hand tap. Your home center should have these in the tool department for a couple of bucks. If you were cutting totally new threads, you would need a tap wrench but since you really will be doing this with your fingers, you probably will not need one. If it is too hard to turn the tap as it gently enters the screw holes, either buy a tap wrench or wrap some tape around the tap to give you a better grip.