Problem: Some Overlay Tools, such as Intersect, return unexpected results or fail


Results do not look correct or operations fail with strange errors such as:

"Invalid Topology [INCOMPLETE_VOID_POLY]".

If this type of error has occurred, it is most likely to occur when using one of the following:
Clip, Erase, Identity, Intersect, Symmetrical Difference, Union, Update, Split Featureclass to Coverage, Dissolve, Feature to Line, Feature To Polygon, Integrate, or ValidateTopology.


It is possible that tool outputs may be strange or incorrect because one or more features in the input feature class have geometry problems. Some examples of geometry problems are:

� short segments
� null geometry
� incorrect ring ordering
� incorrect segment orientation
� unclosed rings
� self-intersections or empty parts

Solution or Workaround

If such errors occur or the output looks incorrect, the first step in assessing the situation is to run the ArcToolbox tool Data Management Tools > Features > Check Geometry.
[O-Image] Check Geometry
This tool provides a list of the invalid features in the feature class and a short description of the problem. Features with problems can be fixed in one of two ways:

  • Editing the feature class with the geometry problem, and fixing each individual problem identified. Some of these problems, like non-simple geometry, can be fixed by double-clicking the feature in the editor and saving the edits.
  • Running the ArcToolBox tool Data Management Tools > Features > Repair Geometry on the feature class containing the problem features.
    [O-Image] Repair Geometry