Ah, thanks Gerry!  I was at a loss at this point.  Debounce could very well do it.

I tried that and it works then I go to try it again and it doesn't

The  x and y work fine  it is just the z axis

I tried that and it works then I go to try it again and it doesn't

Then set it to a higher value.
What did you set it to?

You either have noise, or a bad switch.

The switch is good I tried 1 2 3 4 5 works best at 4 but 1 time it will work the next time it doesn't. I upgraded from windows 7 which it worked fine then I upgraded to windows 10 now it doesn't.

So you're using a motion controller? Which one. The Debounce in General Config has no effect with a motion controller.

K 4030 Kelinger tec

When I set the index debounce to 4 it works the best. It will work once then not work

Yep, sounds like the switch is acting flakey.  Can you swap the upper and lower limit switches to see if that works better?  If not, try doing a "Home Negative" and check if that operates properly.  (CAUTION: Homing to a negative Z requires careful monitoring and quick response on the RESET button if things go awry!)

Thank god that's it hope I got another one