I'm using MB3.
Please tell me the solution in this case.

MB3 is the controller? I am not familiar with this one..

MB3 is BOB.
It is sold at CNC Room in Thailand.

This is an instruction manual.
https://cncroomx.com/wp-content/uploads/downloads/MB3-Owner-Manual-E20R2.pdf

I am sorry, i can't help you with that. You should ask someone/somewhere who knows about that board (MB3).

I understand.
I will also ask the place of purchase.

Please look at the photo.
This is the case for Mach3.
It is displayed as GROUND PRO BE.
Please tell me the meaning.

It is displayed as GROUND PRO BE.
Please tell me the meaning.

This usually means that the probe is triggered. Your probe input send to Mach3/4 that probe hit the material when it shouldn't and that why you get the alarm.

I think MB3 is normal, but is my circuit wrong?

I think MB3 is normal, but is my circuit wrong?

Where you found that circuit?
I can't say if is wrong or right but first time i see two GND to a sensor and a electrolytic capacitor not connected to +V.

Resistors and ceramic capacitors prevent chattering.
Even excluding resistors and ceramic capacitors, it still says "GROUND PROBE".

Resistors and ceramic capacitors prevent chattering.
Even excluding resistors and ceramic capacitors, it still says "GROUND PROBE".

Yes, i understand why are there but i don't see where the + at the capacitor to work for that. I am not an electronic so don't listen to me .
I hope some one else know more about that and help you.

I am almost sure that MACH4 is not your problem here.

I am new to Mach4.
In the case of Mach3, I wrote a script to the button of Aou To Zero and it worked. Does Mach4 work without writing a script?