Index: Ringtoets/ClosingStructures/src/Ringtoets.ClosingStructures.Forms/Views/ClosingStructuresFailureMechanismResultView.cs
===================================================================
diff -u -rb6d6acf62adcb4b23c4c5f6724fbd0091585bbb3 -r83ac738ad69ef53eba6ca4f647657e5b7f024b96
--- Ringtoets/ClosingStructures/src/Ringtoets.ClosingStructures.Forms/Views/ClosingStructuresFailureMechanismResultView.cs	(.../ClosingStructuresFailureMechanismResultView.cs)	(revision b6d6acf62adcb4b23c4c5f6724fbd0091585bbb3)
+++ Ringtoets/ClosingStructures/src/Ringtoets.ClosingStructures.Forms/Views/ClosingStructuresFailureMechanismResultView.cs	(.../ClosingStructuresFailureMechanismResultView.cs)	(revision 83ac738ad69ef53eba6ca4f647657e5b7f024b96)
@@ -55,12 +55,12 @@
                 UpdateDataGridViewDataSource,
                 cg => cg.Children.Concat<object>(cg.Children
                                                    .OfType<StructuresCalculation<ClosingStructuresInput>>()
-                                                   .Select(c => c.InputParameters)));
+                                                   .Select(c => c.InputParameters)).ToArray());
             calculationOutputObserver = new RecursiveObserver<CalculationGroup, ICalculationOutput>(
                 UpdateDataGridViewDataSource,
                 cg => cg.Children.Concat<object>(cg.Children
                                                    .OfType<StructuresCalculation<ClosingStructuresInput>>()
-                                                   .Select(c => c.Output)));
+                                                   .Select(c => c.Output)).ToArray());
             calculationGroupObserver = new RecursiveObserver<CalculationGroup, ICalculationBase>(
                 UpdateDataGridViewDataSource,
                 c => c.Children);