How do I re insatall the probe into an existing program?

Can you take a screenshot of the probe in a program where it works and where it is not working? Of the F9 screen. If possible. 

The only time I have experienced that is if the name of the probe changed.  The probe file will have one name and the program's loadprobe command has a slightly different name listed.  The solution there is to correct the loadprobe command.  

The CMM PC is not connected to the internet.

Nothing about the probe has changed. Can you tell me how to correct the load probe command?

I have verified that the search path is correct.

It might help to change the command to a different probe, then change it again to the probe you want.  

I was going to verify what Cris said above, the names may be slightly different. It also should not have any mathematical symbols in it.

That's the issue. The probe is listed in the command line. But the Probe drop down is blank even when I select it nothing shows. Sometimes it will show A0B0 in the tip box, but if I try to select A0B0 it fades away and vanishes.

This has happened several times in the past. I was hoping there was an obvious fix but I guess I will have to write the entire program again.

Now it did the same thing to another program I used earlier today!

I am not 100% here, but it is possible that your probe file is somehow corrupted. Have you tried making a new one with the same build and angles with a different name?

I can't. There is nothing to select from to build a new probe. Everything is gone. I might try reinstalling the entire software at this point.