I'm working with 8 shapefiles at approximately 63 mb in size total and I am trying to use ArcGIS/arcpy's Union to combine them into one single dataset.
Each time I run this, I get the error:
ERROR 999999: Something unexpected caused the tool to fail. Please refer to the error help for potential solutions, or contact Esri Technical Support http://esriurl.com/support.
Invalid Topology [Incomplete void poly.]
Failed to execute (Union).
On this page, as well as on ESRI's website, it is suggested to use arcgis Repair Geometry to fix this issue. I have tried to run check geometry and repair geometry both with ESRI's validation method and with OGC's validation method. OGC found some errors that it reported solved.
This did however not solve the error.
I have also tried to use v.clean in QGIS 3.2, but this messed up some of the shapefiles geometry (I have a backup, luckily).
Is there some other method i could try?