An item with the same key has already been added

I have just upgraded IdB in TEST to 5.2, and migrated in the Connector and Adapter files from Dev. Dev was already on 5.2 and all connectors are working.

In TEST all of the new Connectors (names "PowerShell HomeFolder*" and "PowerShell MemberOf*") are failing with the error below. The "Powershell Exchange*" connectors work fine (though they already pre-existing in IdB 5.1 before I upgraded to 5.2).

The Connector config file is the same as the one I sent with the previous question. While the error looks very similar to that one it can't be the same - that was a duplicate schema mapping in the connector config, but Powershell connectors don't have schema mapping.

My Import scripts drop a full log of all entity values before running the $entity.Create ... $entity.Commit loop. There are no duplicate sAMAccountNames.

Note that when I did the IdB database upgrade in Test I removed the final lines from the script as told to do here. I don't seem to have had any problems with this in Dev, but thought it worth mentioning.

Change detection engine import all items failed.
Change detection engine import all items for connector PowerShell HomeFolder NMI failed with reason An error occurred while evaluating a task on a worker thread. See the inner exception details for information.. Duration: 00:01:37.5326976
Error details:
Unify.Framework.EvaluatorVisitorException: An error occurred while evaluating a task on a worker thread. See the inner exception details for information. ---> System.ArgumentException: An item with the same key has already been added.
at System.Collections.Generic.Dictionary`2.Insert(TKey key, TValue value, Boolean add)
at System.Linq.Enumerable.ToDictionary[TSource,TKey,TElement](IEnumerable`1 source, Func`2 keySelector, Func`2 elementSelector, IEqualityComparer`1 comparer)
at System.Linq.Enumerable.ToDictionary[TSource,TKey,TElement](IEnumerable`1 source, Func`2 keySelector, Func`2 elementSelector)
at Unify.Product.IdentityBroker.Repository.EntityLinqQueryConverterUtilitiesBase`4.GetCollectionKeyData(TEntityKey key, EntityDataContext sourceContext)
at Unify.Product.IdentityBroker.Repository.EntitySingleValueDataUtilityBase`2.CreateEntityValue(TEntityKey key, IValue value, IEntityCollectionKeyUtility`1 collectionKeyUtility, EntityDataSet set, __EntityInsertRow row, EntityDataContext sourceContext)
at Unify.Product.IdentityBroker.Repository.KnownEntityContextBase`4.ConvertEntityValueToDataValue(KeyValuePair`2 entityValueAndKey, __EntityInsertRow row, EntityDataSet entityDataSet, EntityDataContext sourceContext)
at Unify.Product.IdentityBroker.Repository.KnownEntityContextBase`4.<>c__DisplayClass31_0.<convertitemtovalues>b__0(KeyValuePair`2 entityValueAndKey)
at System.Linq.Enumerable.WhereSelectEnumerableIterator`2.MoveNext()
at System.Linq.Enumerable.<selectmanyiterator>d__16`2.MoveNext()
at Unify.Framework.Visitor.Visit[T](IEnumerable`1 visitCollection, Action`2 visitor)
at Unify.Product.IdentityBroker.Repository.KnownEntityContextBase`4.InsertItems(ISet`1 addedItems, EntityDataContext sourceContext, SqlConnection connection)
at Unify.Framework.Data.LinqContextConversionBase`4.SubmitChanges()
at Unify.Product.IdentityBroker.SaveChangedEntitiesTransformationUnit.Transform(IDictionaryTwoPassDifferenceReport`4 input)
at Unify.Product.IdentityBroker.RepositoryChangeDetectionWorkerBase.PerformChangeDetectionOnConnectorEntityPage(IEnumerable`1 connectorEntities, Int32& index, Int32 entitiesProcessedSoFar, IEntityChangesReportGenerator`2 reportGenerator, IHashSet`1 seenKeys)
at Unify.Product.IdentityBroker.RepositoryChangeDetectionWorkerBase.<>c__DisplayClass11_0.<performchangedetection>b__0(IEnumerable`1 page)
at Unify.Framework.Visitor.ThreadsafeVisitorEvaluator`1.ThreadsafeItemEvaluator.Evaluate()
--- End of inner exception stack trace ---
at Unify.Framework.Visitor.ThreadsafeVisitorEvaluator`1.CheckForException()
at Unify.Framework.Visitor.ThreadsafeVisitorEvaluator`1.Visit()
at Unify.Product.IdentityBroker.RepositoryChangeDetectionWorkerBase.PerformChangeDetection(IEnumerable`1 connectorEntities)
at Unify.Product.IdentityBroker.ChangeDetectionImportAllJob.ImportAllChangeProcess()
at Unify.Product.IdentityBroker.ChangeDetectionImportAllJob.RunBase()
at Unify.Framework.DefinedScopeJobAuditTrailJobDecorator.Run()
at Unify.Product.IdentityBroker.ConnectorJobExecutor.<>c__DisplayClass30_0.<run>b__0()
at Unify.Framework.<span class="redactor-selection-marker" id="selection-marker-1"></span>AsynchronousJobExecutor.PerformJobCallback(Object state)
</run></performchangedetection></selectmanyiterator></convertitemtovalues>