Index: Ringtoets/ClosingStructures/test/Ringtoets.ClosingStructures.Service.Test/ClosingStructuresCalculationServiceTest.cs
===================================================================
diff -u -r440f228de8eb72ed5be40270b20a46113917333e -rf70611f9af51a6ffc8cb4d8d28d1ea806104937b
--- Ringtoets/ClosingStructures/test/Ringtoets.ClosingStructures.Service.Test/ClosingStructuresCalculationServiceTest.cs	(.../ClosingStructuresCalculationServiceTest.cs)	(revision 440f228de8eb72ed5be40270b20a46113917333e)
+++ Ringtoets/ClosingStructures/test/Ringtoets.ClosingStructures.Service.Test/ClosingStructuresCalculationServiceTest.cs	(.../ClosingStructuresCalculationServiceTest.cs)	(revision f70611f9af51a6ffc8cb4d8d28d1ea806104937b)
@@ -408,6 +408,7 @@
                 Assert.AreEqual(0, calculationInputs.Length);
                 var exception = Assert.Throws<InvalidEnumArgumentException>(call);
                 Assert.AreEqual("calculation", exception.ParamName);
+                StringAssert.StartsWith("The value of argument 'calculation' (100) is invalid for Enum type 'ClosingStructureInflowModelType'.", exception.Message);
             }
             mockRepository.VerifyAll();
         }