Some families have become unusable. Reload the families, or delete them from the model.
Namespace: Autodesk.Revit.DB
Assembly: RevitAPI (in RevitAPI.dll) Version: 26.1.0.0 (26.1.0.34)
Syntax
C#
public static FailureDefinitionId UnableToUpgradeDueToCorruptFamilies { get; }