Index: DamEngine/trunk/src/Deltares.DamEngine.IntegrationTests/IntegrationTests/DesignCalculatorTests.cs
===================================================================
diff -u -r3365 -r3403
--- DamEngine/trunk/src/Deltares.DamEngine.IntegrationTests/IntegrationTests/DesignCalculatorTests.cs	(.../DesignCalculatorTests.cs)	(revision 3365)
+++ DamEngine/trunk/src/Deltares.DamEngine.IntegrationTests/IntegrationTests/DesignCalculatorTests.cs	(.../DesignCalculatorTests.cs)	(revision 3403)
@@ -62,7 +62,7 @@
             Assert.IsNotNull(engineInterface.DamProjectData);
             string outputString = engineInterface.Run();
             var output = DamXmlSerialization.LoadOutputFromXmlString(outputString);
-            // As DGeoSTbaility is no longer available, calculation fails with missing "kernel" (1 error).
+            // As DGeoStability is no longer available, calculation fails with missing "kernel" (1 error).
             Assert.AreEqual(1, output.Results.CalculationMessages.Length);
             Assert.IsTrue(output.Results.CalculationMessages[0].Message1.Contains("Gekozen rekenkernel is nog niet beschikbaar"));
         }
Index: DamEngine/trunk/src/Deltares.DamEngine.Calculators/DikesDesign/DesignCalculator.cs
===================================================================
diff -u -r2799 -r3403
--- DamEngine/trunk/src/Deltares.DamEngine.Calculators/DikesDesign/DesignCalculator.cs	(.../DesignCalculator.cs)	(revision 2799)
+++ DamEngine/trunk/src/Deltares.DamEngine.Calculators/DikesDesign/DesignCalculator.cs	(.../DesignCalculator.cs)	(revision 3403)
@@ -81,9 +81,10 @@
                     for (int subSoilScenarioIndex = 0; subSoilScenarioIndex < location.Segment.SoilProfileProbabilities.Count; subSoilScenarioIndex++)
                     {
                         // Check if the subSoilScenario is applicable for the failuremechanism that is being calculated
-                        if (location.Segment.SoilProfileProbabilities[subSoilScenarioIndex].SegmentFailureMechanismType.Value.In(
+                        if (location.Segment.SoilProfileProbabilities[subSoilScenarioIndex].SegmentFailureMechanismType.HasValue && 
+                            (location.Segment.SoilProfileProbabilities[subSoilScenarioIndex].SegmentFailureMechanismType.Value.In(
                             ConversionHelper.ConvertToSegmentFailureMechanismType(damProjectData.DamProjectCalculationSpecification.CurrentSpecification.FailureMechanismSystemType),
-                            SegmentFailureMechanismType.All))
+                            SegmentFailureMechanismType.All)))
                         {
                             var soiProfileProbability = location.Segment.SoilProfileProbabilities[subSoilScenarioIndex];
                             for (int designScenarioIndex = 0; designScenarioIndex < location.Scenarios.Count; designScenarioIndex++)