Exception Info: An exception occurred during the operation, making the result invalid.  Check InnerException for exception details. 
 
   at System.Collections.Generic.Dictionary`2.ValueCollection.Enumerator.MoveNext()
   at System.Linq.Parallel.PartitionedDataSource`1.ContiguousChunkLazyEnumerator.MoveNext(T& currentElement, Int32& currentKey)
   at System.Linq.Parallel.SelectQueryOperator`2.SelectQueryOperatorEnumerator`1.MoveNext(TOutput& currentElement, TKey& currentKey)
   at System.Linq.Parallel.SelectQueryOperator`2.SelectQueryOperatorEnumerator`1.MoveNext(TOutput& currentElement, TKey& currentKey)
   at System.Linq.Parallel.HashRepartitionEnumerator`3.EnumerateAndRedistributeElements()
   at System.Linq.Parallel.HashRepartitionEnumerator`3.MoveNext(Pair`2& currentElement, Int32& currentKey)
   at System.Linq.Parallel.UnionQueryOperator`1.UnionQueryOperatorEnumerator`2.MoveNext(TInputOutput& currentElement, Int32& currentKey)
   at System.Linq.Parallel.SortQueryOperatorEnumerator`3.MoveNext(TInputOutput& currentElement, TSortKey& currentKey)
   at System.Linq.Parallel.SortHelper`2.BuildKeysFromSource(GrowingArray`1& keys, List`1& values)
   at System.Linq.Parallel.SortHelper`2.Sort()
   at System.Linq.Parallel.OrderPreservingSpoolingTask`2.SpoolingWork()
   at System.Linq.Parallel.SpoolingTaskBase.Work()
   at System.Linq.Parallel.QueryTask.BaseWork(Object unused)
   at System.Threading.Tasks.Task.Execute()