Tin foil works. You crumple it up gently and place it on the edge of the counter where your cat can see it from below. You have to keep it there for a few weeks. Then, move it further back so the cat cannot see it from below but encounters the foil once they jump up. Then, THEY ARE CURED! (until they find another high place to jump up).
Visitors may think you are a little wacky
when they see all the tin foil all over your counters, buffets, etc., but it does work.