Error: Scanline Start Point Outside of Part Boundary

While executing a Ansys Additive Print simulation, what does the following error imply, “Scanline start point outside of part boundary…”? 

This error means that the slicing application that creates the scan patterns created at least one scan line outside the part boundaries. This can happen if the part stl file is not clean, meaning the triangles enclosing the geometry are not completely watertight or have intersections or some other issue.