Mismatch of border Segments (REGNODPOL)

Error Message

Running the ARC CLEAN command or the Clean tool from the ArcToolbox Data Management Topology menu against a polygon coverage returns the following error message while assembling polygons:

"FATAL ERROR
Mismatch of border Segments (REGNODPOL)Bailing out of Build"

Cause

The MSK or MSK.ADF file in the coverage directory is corrupt.

Solution or Workaround

1. Use the operating system file manager to delete the MSK or MSK.ADF file in the coverage directory.
2. Run the ARC CLEAN command or the ArcToolbox CLEAN tool against the coverage.