When I'm trying to dissolve a polygon through an arcpy script the operation fails with the 999999 error on computers with small amount of RAM [~3 GB] (known issue). Unfortunately neither this, that ...
TL;DR I can't get an installation free version of GDAL/OGR to work from within ArcMap 10.0. I get an ImportError: DLL load failed on _mod = imp.load_module('_gdal', fp, pathname, description). ...