Index: Ringtoets/ClosingStructures/src/Ringtoets.ClosingStructures.Plugin/ClosingStructuresPlugin.cs
===================================================================
diff -u -r87234360c430570d06bfa618b1b9a18a8d2b7219 -r13d2467395297546782053ebed2bb9f78707fe30
--- Ringtoets/ClosingStructures/src/Ringtoets.ClosingStructures.Plugin/ClosingStructuresPlugin.cs	(.../ClosingStructuresPlugin.cs)	(revision 87234360c430570d06bfa618b1b9a18a8d2b7219)
+++ Ringtoets/ClosingStructures/src/Ringtoets.ClosingStructures.Plugin/ClosingStructuresPlugin.cs	(.../ClosingStructuresPlugin.cs)	(revision 13d2467395297546782053ebed2bb9f78707fe30)
@@ -567,7 +567,7 @@
         {
             var contextMenuEnabled = true;
             string toolTipMessage = RingtoetsCommonFormsResources.StructuresPlugin_CreateUpdateStructureItem_Update_all_calculations_with_Structure_Tooltip;
-            IEnumerable<StructuresCalculation<ClosingStructuresInput>> calculationsToUpdate = calculations
+            IList<StructuresCalculation<ClosingStructuresInput>> calculationsToUpdate = calculations
                 .Where(c => c.InputParameters.Structure != null && !c.InputParameters.IsStructureInputSynchronized)
                 .ToList();
 
@@ -580,13 +580,13 @@
             return new StrictContextMenuItem(RingtoetsCommonFormsResources.StructuresPlugin_CreateUpdateStructureItem_Update_all_Structures,
                                              toolTipMessage,
                                              RingtoetsCommonFormsResources.UpdateItemIcon,
-                                             (o, args) => UpdateStructureDependentDataOfCalculations(calculations))
+                                             (o, args) => UpdateStructureDependentDataOfCalculations(calculationsToUpdate))
             {
                 Enabled = contextMenuEnabled
             };
         }
 
-        private void UpdateStructureDependentDataOfCalculations(IEnumerable<StructuresCalculation<ClosingStructuresInput>> calculations)
+        private void UpdateStructureDependentDataOfCalculations(IList<StructuresCalculation<ClosingStructuresInput>> calculations)
         {
             string message =
                 RingtoetsCommonFormsResources.StructuresPlugin_VerifyStructureUpdate_Confirm_calculation_outputs_cleared_when_updating_Structure_dependent_data;