Illegal Operation in module MSVCRT20.DLL

Last Published: April 25, 2020

Error Message

ArcView returns this error when opening a project that had a shapefile auto-labeled when opened the last time:

"Illegal Operation in module MSVCRT20.DLL"


The shapefile that you auto-label was generated by converting an ArcInfo coverage to a shapefile. The coverage may have contained sliver polygons.

Solution or Workaround

Build and clean the Polygon coverage to get rid of the sliver polygons. Then, convert the coverage to a shapefile and auto-label.

Article ID:000003617

  • Legacy Products

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