Unclosed polygon border (ARCPAL)

Last Published: April 25, 2020

Solution or Workaround


CLEAN, BUILD, MAPJOIN, or any Overlay Module command returns this message:

   Assembling polygons...
Unclosed polygon border (ARCPAL)


This is usually a result of a corrupted MSK file.


Option 1: Delete the .MSK file from the coverage before using CLEAN or BUILD.

Option 2: Increase fuzzy tolerance by 1.5 or decrease it by .25. Adjust fuzzy tolerance until the situation no longer occurs.

Since MAPJOIN does not have an option for {fuzzy_tolerance}, use the Starter Kit command TOLERANCE to adjust this value in each coverage's TOL file. MAPJOIN uses the value set in TOL to determine the tolerance.

Article ID:000001621

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