The result references a custom script tool that imports or adds a toolbox which is either inaccessible or does not exist.
Ensure your Python script is correctly referencing the toolbox and the toolbox is accessible. Some possible reasons the import failed include the following:
- The toolbox does not exist.
- Syntax error or typo in the path reference to toolbox.
Ensure arcpy.ImportToolbox or arcpy.AddToolbox is used correctly and the toolbox exists.