Description
The tool was unable to transform the Candidate Features into the output coordinate system defined by the current environment settings. If you are trying to send the output to a feature dataset, a feature dataset requires that all feature classes share a common coordinate system and the tool was unable to transform the Candidate Features into the required output coordinate system defined by the feature dataset.
Solution
Consider reprojecting your Candidate Features or, if that is not possible, sending the output to a different location.