Index: Ringtoets/StabilityPointStructures/src/Ringtoets.StabilityPointStructures.Forms/Properties/AssemblyInfo.cs
===================================================================
diff -u -r0819cf01b494097b764677be8dd47853e38fc223 -r3433a40820d60930e9664efc6e0fa6d8c814a50e
--- Ringtoets/StabilityPointStructures/src/Ringtoets.StabilityPointStructures.Forms/Properties/AssemblyInfo.cs	(.../AssemblyInfo.cs)	(revision 0819cf01b494097b764677be8dd47853e38fc223)
+++ Ringtoets/StabilityPointStructures/src/Ringtoets.StabilityPointStructures.Forms/Properties/AssemblyInfo.cs	(.../AssemblyInfo.cs)	(revision 3433a40820d60930e9664efc6e0fa6d8c814a50e)
@@ -20,6 +20,8 @@
 // All rights reserved.
 
 using System.Reflection;
+using System.Runtime.CompilerServices;
 
 [assembly: AssemblyTitle("Ringtoets.StabilityPointStructures.Forms")]
-[assembly: AssemblyProduct("Ringtoets.StabilityPointStructures.Forms")]
\ No newline at end of file
+[assembly: AssemblyProduct("Ringtoets.StabilityPointStructures.Forms")]
+[assembly: InternalsVisibleTo("Ringtoets.StabilityPointStructures.Forms.Test")]
\ No newline at end of file
Index: Ringtoets/StabilityPointStructures/src/Ringtoets.StabilityPointStructures.Forms/Views/StabilityPointStructuresFailureMechanismSectionResultRow.cs
===================================================================
diff -u -r692f5c99e9c731c67502c08146cf7d1b87e214ad -r3433a40820d60930e9664efc6e0fa6d8c814a50e
--- Ringtoets/StabilityPointStructures/src/Ringtoets.StabilityPointStructures.Forms/Views/StabilityPointStructuresFailureMechanismSectionResultRow.cs	(.../StabilityPointStructuresFailureMechanismSectionResultRow.cs)	(revision 692f5c99e9c731c67502c08146cf7d1b87e214ad)
+++ Ringtoets/StabilityPointStructures/src/Ringtoets.StabilityPointStructures.Forms/Views/StabilityPointStructuresFailureMechanismSectionResultRow.cs	(.../StabilityPointStructuresFailureMechanismSectionResultRow.cs)	(revision 3433a40820d60930e9664efc6e0fa6d8c814a50e)
@@ -328,12 +328,22 @@
 
         private void UpdateDerivedData()
         {
+            ResetErrorTexts();
             TryGetSimpleAssemblyCategoryGroup();
             TryGetDetailedAssemblyCategoryGroup();
             TryGetTailorMadeAssemblyCategoryGroup();
             TryGetCombinedAssemblyCategoryGroup();
         }
 
+        private void ResetErrorTexts()
+        {
+            ColumnStateDefinitions[simpleAssemblyCategoryGroupIndex].ErrorText = string.Empty;
+            ColumnStateDefinitions[detailedAssemblyCategoryGroupIndex].ErrorText = string.Empty;
+            ColumnStateDefinitions[tailorMadeAssemblyCategoryGroupIndex].ErrorText = string.Empty;
+            ColumnStateDefinitions[combinedAssemblyCategoryGroupIndex].ErrorText = string.Empty;
+            ColumnStateDefinitions[combinedAssemblyProbabilityIndex].ErrorText = string.Empty;
+        }
+
         private void TryGetSimpleAssemblyCategoryGroup()
         {
             try
@@ -343,6 +353,7 @@
             catch (AssemblyException e)
             {
                 simpleAssemblyCategoryGroup = FailureMechanismSectionAssemblyCategoryGroup.None;
+                ColumnStateDefinitions[simpleAssemblyCategoryGroupIndex].ErrorText = e.Message;
             }
         }
 
@@ -358,6 +369,7 @@
             catch (AssemblyException e)
             {
                 detailedAssemblyCategoryGroup = FailureMechanismSectionAssemblyCategoryGroup.None;
+                ColumnStateDefinitions[detailedAssemblyCategoryGroupIndex].ErrorText = e.Message;
             }
         }
 
@@ -373,6 +385,7 @@
             catch (AssemblyException e)
             {
                 tailorMadeAssemblyCategoryGroup = FailureMechanismSectionAssemblyCategoryGroup.None;
+                ColumnStateDefinitions[tailorMadeAssemblyCategoryGroupIndex].ErrorText = e.Message;
             }
         }
 
@@ -393,6 +406,8 @@
             {
                 combinedAssemblyCategoryGroup = FailureMechanismSectionAssemblyCategoryGroup.None;
                 CombinedAssemblyProbability = double.NaN;
+                ColumnStateDefinitions[combinedAssemblyCategoryGroupIndex].ErrorText = e.Message;
+                ColumnStateDefinitions[combinedAssemblyProbabilityIndex].ErrorText = e.Message;
             }
         }
 
Index: Ringtoets/StabilityPointStructures/test/Ringtoets.StabilityPointStructures.Forms.Test/Views/StabilityPointStructuresFailureMechanismSectionResultRowTest.cs
===================================================================
diff -u -r692f5c99e9c731c67502c08146cf7d1b87e214ad -r3433a40820d60930e9664efc6e0fa6d8c814a50e
--- Ringtoets/StabilityPointStructures/test/Ringtoets.StabilityPointStructures.Forms.Test/Views/StabilityPointStructuresFailureMechanismSectionResultRowTest.cs	(.../StabilityPointStructuresFailureMechanismSectionResultRowTest.cs)	(revision 692f5c99e9c731c67502c08146cf7d1b87e214ad)
+++ Ringtoets/StabilityPointStructures/test/Ringtoets.StabilityPointStructures.Forms.Test/Views/StabilityPointStructuresFailureMechanismSectionResultRowTest.cs	(.../StabilityPointStructuresFailureMechanismSectionResultRowTest.cs)	(revision 3433a40820d60930e9664efc6e0fa6d8c814a50e)
@@ -287,6 +287,66 @@
         }
 
         [Test]
+        public void GivenRowWithAssemblyErrors_WhenUpdatingAndAssemblyDoesNotThrowException_ExpectedColumnStates()
+        {
+            // Given
+            var random = new Random(39);
+            var failureMechanism = new StabilityPointStructuresFailureMechanism();
+
+            var mocks = new MockRepository();
+            IAssessmentSection assessmentSection = AssessmentSectionHelper.CreateAssessmentSectionStub(failureMechanism, mocks);
+            mocks.ReplayAll();
+
+            FailureMechanismSection section = FailureMechanismSectionTestFactory.CreateFailureMechanismSection();
+            var result = new StabilityPointStructuresFailureMechanismSectionResult(section);
+
+            using (new AssemblyToolCalculatorFactoryConfig())
+            {
+                var calculatorfactory = (TestAssemblyToolCalculatorFactory)AssemblyToolCalculatorFactory.Instance;
+                FailureMechanismSectionAssemblyCalculatorStub calculator = calculatorfactory.LastCreatedFailureMechanismSectionAssemblyCalculator;
+                calculator.ThrowExceptionOnCalculate = true;
+                calculator.SimpleAssessmentAssemblyOutput = new FailureMechanismSectionAssembly(
+                    random.NextDouble(),
+                    random.NextEnumValue<FailureMechanismSectionAssemblyCategoryGroup>());
+                calculator.DetailedAssessmentAssemblyOutput = new FailureMechanismSectionAssembly(
+                    random.NextDouble(),
+                    random.NextEnumValue<FailureMechanismSectionAssemblyCategoryGroup>());
+                calculator.TailorMadeAssessmentAssemblyOutput = new FailureMechanismSectionAssembly(
+                    random.NextDouble(),
+                    random.NextEnumValue<FailureMechanismSectionAssemblyCategoryGroup>());
+                calculator.CombinedAssemblyOutput = new FailureMechanismSectionAssembly(
+                    random.NextDouble(),
+                    random.NextEnumValue<FailureMechanismSectionAssemblyCategoryGroup>());
+
+                var row = new StabilityPointStructuresFailureMechanismSectionResultRow(result, failureMechanism, assessmentSection,
+                                                                                ConstructionProperties);
+
+                // Precondition
+                IDictionary<int, DataGridViewColumnStateDefinition> columnStateDefinitions = row.ColumnStateDefinitions;
+                const string expectedErrorText = "Message";
+
+                Assert.AreEqual(expectedErrorText, columnStateDefinitions[ConstructionProperties.SimpleAssemblyCategoryGroupIndex].ErrorText);
+                Assert.AreEqual(expectedErrorText, columnStateDefinitions[ConstructionProperties.DetailedAssemblyCategoryGroupIndex].ErrorText);
+                Assert.AreEqual(expectedErrorText, columnStateDefinitions[ConstructionProperties.TailorMadeAssemblyCategoryGroupIndex].ErrorText);
+                Assert.AreEqual(expectedErrorText, columnStateDefinitions[ConstructionProperties.CombinedAssemblyCategoryGroupIndex].ErrorText);
+                Assert.AreEqual(expectedErrorText, columnStateDefinitions[ConstructionProperties.CombinedAssemblyProbabilityIndex].ErrorText);
+
+                // When
+                calculator.ThrowExceptionOnCalculate = false;
+                row.SimpleAssessmentResult = SimpleAssessmentResultValidityOnlyType.Applicable;
+
+                // Then
+                Assert.AreEqual(string.Empty, columnStateDefinitions[ConstructionProperties.SimpleAssemblyCategoryGroupIndex].ErrorText);
+                Assert.AreEqual(string.Empty, columnStateDefinitions[ConstructionProperties.DetailedAssemblyCategoryGroupIndex].ErrorText);
+                Assert.AreEqual(string.Empty, columnStateDefinitions[ConstructionProperties.TailorMadeAssemblyCategoryGroupIndex].ErrorText);
+                Assert.AreEqual(string.Empty, columnStateDefinitions[ConstructionProperties.CombinedAssemblyCategoryGroupIndex].ErrorText);
+                Assert.AreEqual(string.Empty, columnStateDefinitions[ConstructionProperties.CombinedAssemblyProbabilityIndex].ErrorText);
+
+                mocks.VerifyAll();
+            }
+        }
+
+        [Test]
         public void UseManualAssemblyProbability_SetNewValue_NotifyObserversAndPropertyChanged()
         {
             // Setup