I just wanted to thank all the contributors to this thread.

My Harmony 628 was experiencing the same problems explained in this thread. One of the six buttons (alongside the screen) had actually stopped working months ago. I was just doing various work-arounds to avoid needing to use that particular button. But then, slowly but surely, other buttons started to get difficult to work until some of the more crucial buttons were quickly dying.

I could not find a local vendor for the Caikote 44, so I figured to try the aluminum tape. I actually printed up the .jpg of the HVAC tape and took it to my local Lowe's & Home Depot. I ended up with a much larger role (but the smallest either store had) for $7.50. I'll be able to fix RC buttons for the next trillion years!

I took apart the remote. The 628 has six screws to deal with (four to take apart the plastic case and two holding the IC board to the front plastic panel of the remote). Then, after some exasperating sessions cutting the tape into extremely small pieces and using tweezers to affix it to the buttons, the remote worked just like new. Too cool for school.

It's hard for me to believe I allowed that one button to be inoperative for so long.

It seems like a pretty major design flaw for these things to be crapping out after only a couple year's use. Hopefully they've changed the design on more current models.