diff --git a/libsrc/meshing/meshclass.cpp b/libsrc/meshing/meshclass.cpp
index d2431c5f..031cd766 100644
--- a/libsrc/meshing/meshclass.cpp
+++ b/libsrc/meshing/meshclass.cpp
@@ -163,7 +163,7 @@ namespace netgen
         if(mesh.PointContainedIn2DElement(p,lami,ii))
           return ii;
       }
-    return 0;
+    return SurfaceElementIndex::INVALID;
   }
 
   SegmentIndex Find1dElement (const Mesh& mesh,