That is an irritating warning, isn't it?
It doesn't, in general, indicate any actual problem. There isn't a lot you can do about it, apart from write your probes to always produce some output.
Most of us just put up with it.
You can modify your probes to always generate some output.
If they are out of the box probes, we could probably complain and log a problem: this out of the box probe constantly returns no results. I probably should, but I'm afraid I've gotten used to ignoring this one.
- Tim.
