Has anyone ever seen this before?

The prefetch path element at index 0 in the passed in prefetch path for root entity type 2 is meant for root entity type 4 which isn't a subtype of 2

Code looks like this

    IEntityCollection2 sensitivities = new EntityCollection(new ResourceItemsSensitivitiesEntityFactory());
    RelationPredicateBucket relationPredicateBucket = new RelationPredicateBucket();
    IPredicateExpression filter = new PredicateExpression();
    filter.Add(PredicateFactory.CompareValue(ResourceItemsSensitivitiesFieldIndex.ResourceItemSensitivityData,
        ComparisonOperator.Equal,section));
    relationPredicateBucket.PredicateExpression.Add(filter);
    IPrefetchPath2 prefetchPath = new PrefetchPath2((int)EntityType.ResourceItemsEntity);
    prefetchPath.Add(ResourceItemsSensitivitiesEntity.PrefetchPathResourceItemSensitivityTypes);
    Adapter adapter = new Adapter();
    adapter.FetchEntityCollection(sensitivities, relationPredicateBucket, prefetchPath);

Thanks! Bob

Please use the following line:

IPrefetchPath2 prefetchPath = new PrefetchPath2((int)EntityType.ResourceItemsSensitivitiesEntity);

instead of:

IPrefetchPath2 prefetchPath = new PrefetchPath2((int)EntityType.ResourceItemsEntity);

ah, silly me. Thanks!