Problem: The network loader may create invalid network features during a geometric network creation
During the creation of a geometric network, the network loader can modify network features, such that they have invalid network geometry with identical start and stop vertices.
If the start and stop vertices of a line feature are within the snapping tolerance specified in the geometric network creation wizard, the start and stop vertices are snapped to each other. This creates a network feature whose geometry is invalid within the geometric network. A table is created at the workspace level with the name <Network Name>_BUILDERR, and a record for the feature is added to the table with the error type 12.
Solution or Workaround
Option 1: When building the network, set the snapping tolerance to a value that is less than the distance between the start and stop vertices of the line features in the network.
Option 2: After the network has been built, modify the invalid feature’s geometry, so it is no longer a loop feature.
For information on modifying invalid features, see Repairing network topology in the ArcGIS Desktop Help under Geodatabases > Editing your geodatabase.