Index: Riskeer/MacroStabilityInwards/src/Riskeer.MacroStabilityInwards.IO/Exporters/MacroStabilityInwardsCalculationGroupExporter.cs
===================================================================
diff -u -re6972847cef019302b4fe9f7dd45d09175ef6cea -r6f3f5cd43feafa96fdedaeb2ccb01240c4261de1
--- Riskeer/MacroStabilityInwards/src/Riskeer.MacroStabilityInwards.IO/Exporters/MacroStabilityInwardsCalculationGroupExporter.cs	(.../MacroStabilityInwardsCalculationGroupExporter.cs)	(revision e6972847cef019302b4fe9f7dd45d09175ef6cea)
+++ Riskeer/MacroStabilityInwards/src/Riskeer.MacroStabilityInwards.IO/Exporters/MacroStabilityInwardsCalculationGroupExporter.cs	(.../MacroStabilityInwardsCalculationGroupExporter.cs)	(revision 6f3f5cd43feafa96fdedaeb2ccb01240c4261de1)
@@ -105,8 +105,8 @@
             CreateDirectory(currentFolderPath);
 
             var continueExport = true;
-            var exportedGroups = new List<CalculationGroup>();
-            var exportedCalculations = new List<MacroStabilityInwardsCalculation>();
+            var exportedGroups = new Dictionary<CalculationGroup, string>();
+            var exportedCalculations = new Dictionary<MacroStabilityInwardsCalculation, string>();
 
             foreach (ICalculationBase calculationItem in groupToExport.Children)
             {
@@ -148,25 +148,27 @@
             }
         }
 
-        private bool ExportCalculationGroup(CalculationGroup nestedGroup, string currentFolderPath, ICollection<CalculationGroup> exportedGroups)
+        private bool ExportCalculationGroup(CalculationGroup nestedGroup, string currentFolderPath, IDictionary<CalculationGroup, string> exportedGroups)
         {
-            string uniqueGroupName = NamingHelper.GetUniqueName(exportedGroups, nestedGroup.Name, group => group.Name);
+            string uniqueGroupName = NamingHelper.GetUniqueName(exportedGroups, nestedGroup.Name, group => group.Value);
 
             bool exportSucceeded = ExportCalculationItemsRecursively(nestedGroup, Path.Combine(currentFolderPath, uniqueGroupName));
             if (!exportSucceeded)
             {
                 return false;
             }
 
-            exportedGroups.Add(nestedGroup);
+            exportedGroups.Add(nestedGroup, uniqueGroupName);
             return true;
         }
 
-        private bool ExportCalculation(MacroStabilityInwardsCalculation calculation, string currentFolderPath, ICollection<MacroStabilityInwardsCalculation> exportedCalculations)
+        private bool ExportCalculation(MacroStabilityInwardsCalculation calculation, string currentFolderPath, IDictionary<MacroStabilityInwardsCalculation, string> exportedCalculations)
         {
             log.InfoFormat(CoreCommonGuiResources.GuiExportHandler_ExportItemUsingDialog_Start_exporting_DataType_0_, calculation.Name);
 
-            string filePath = GetCalculationFilePath(calculation, currentFolderPath, exportedCalculations);
+            string uniqueName = NamingHelper.GetUniqueName(exportedCalculations, ((ICalculationBase)calculation).Name, c => c.Value);
+            string filePath = GetCalculationFilePath(currentFolderPath, uniqueName);
+
             var exporter = new MacroStabilityInwardsCalculationExporter(calculation, persistenceFactory, filePath, () => getNormativeAssessmentLevelFunc(calculation));
 
             bool exportSucceeded = exporter.Export();
@@ -177,14 +179,13 @@
             }
 
             log.InfoFormat(Resources.MacroStabilityInwardsCalculationGroupExporter_Export_Data_from_0_exported_to_file_1, calculation.Name, filePath);
-            exportedCalculations.Add(calculation);
+            exportedCalculations.Add(calculation, uniqueName);
             return true;
         }
 
-        private string GetCalculationFilePath(ICalculationBase calculation, string currentFolderPath, IEnumerable<MacroStabilityInwardsCalculation> exportedCalculations)
+        private string GetCalculationFilePath(string currentFolderPath, string fileName)
         {
-            string uniqueName = NamingHelper.GetUniqueName(exportedCalculations, calculation.Name, c => c.Name);
-            string fileNameWithExtension = $"{uniqueName}.{fileExtension}";
+            string fileNameWithExtension = $"{fileName}.{fileExtension}";
             return Path.Combine(currentFolderPath, fileNameWithExtension);
         }
     }
Index: Riskeer/MacroStabilityInwards/test/Riskeer.MacroStabilityInwards.IO.Test/Exporters/MacroStabilityInwardsCalculationGroupExporterTest.cs
===================================================================
diff -u -re6972847cef019302b4fe9f7dd45d09175ef6cea -r6f3f5cd43feafa96fdedaeb2ccb01240c4261de1
--- Riskeer/MacroStabilityInwards/test/Riskeer.MacroStabilityInwards.IO.Test/Exporters/MacroStabilityInwardsCalculationGroupExporterTest.cs	(.../MacroStabilityInwardsCalculationGroupExporterTest.cs)	(revision e6972847cef019302b4fe9f7dd45d09175ef6cea)
+++ Riskeer/MacroStabilityInwards/test/Riskeer.MacroStabilityInwards.IO.Test/Exporters/MacroStabilityInwardsCalculationGroupExporterTest.cs	(.../MacroStabilityInwardsCalculationGroupExporterTest.cs)	(revision 6f3f5cd43feafa96fdedaeb2ccb01240c4261de1)
@@ -364,11 +364,13 @@
             MacroStabilityInwardsCalculationScenario calculation1 = CreateCalculation("calculation1");
             MacroStabilityInwardsCalculationScenario calculation2 = CreateCalculation("calculation2");
             MacroStabilityInwardsCalculationScenario calculation3 = CreateCalculation("calculation1");
+            MacroStabilityInwardsCalculationScenario calculation4 = CreateCalculation("calculation1");
 
             var calculationGroup = new CalculationGroup();
             calculationGroup.Children.Add(calculation1);
             calculationGroup.Children.Add(calculation2);
             calculationGroup.Children.Add(calculation3);
+            calculationGroup.Children.Add(calculation4);
 
             var exporter = new MacroStabilityInwardsCalculationGroupExporter(calculationGroup, new PersistenceFactory(), folderPath, fileExtension, c => AssessmentSectionTestHelper.GetTestAssessmentLevel());
 
@@ -384,6 +386,7 @@
                     AssertCalculationExists(Path.Combine(folderPath, $"{calculation1.Name}.{fileExtension}"));
                     AssertCalculationExists(Path.Combine(folderPath, $"{calculation2.Name}.{fileExtension}"));
                     AssertCalculationExists(Path.Combine(folderPath, $"{calculation3.Name} (1).{fileExtension}"));
+                    AssertCalculationExists(Path.Combine(folderPath, $"{calculation4.Name} (2).{fileExtension}"));
                 }
             }
             finally
@@ -402,6 +405,8 @@
             MacroStabilityInwardsCalculationScenario calculation1 = CreateCalculation("calculation1");
             MacroStabilityInwardsCalculationScenario calculation2 = CreateCalculation("calculation2");
             MacroStabilityInwardsCalculationScenario calculation3 = CreateCalculation("calculation1");
+            MacroStabilityInwardsCalculationScenario calculation4 = CreateCalculation("calculation1");
+            MacroStabilityInwardsCalculationScenario calculation5 = CreateCalculation("calculation1");
 
             var rootGroup = new CalculationGroup
             {
@@ -415,11 +420,18 @@
             {
                 Name = "group1"
             };
+            var nestedGroup3 = new CalculationGroup
+            {
+                Name = "group1"
+            };
             nestedGroup1.Children.Add(calculation1);
             nestedGroup1.Children.Add(calculation2);
             nestedGroup2.Children.Add(calculation3);
+            nestedGroup2.Children.Add(calculation4);
+            nestedGroup3.Children.Add(calculation5);
             rootGroup.Children.Add(nestedGroup1);
             rootGroup.Children.Add(nestedGroup2);
+            rootGroup.Children.Add(nestedGroup3);
 
             var exporter = new MacroStabilityInwardsCalculationGroupExporter(rootGroup, new PersistenceFactory(), folderPath, fileExtension, c => AssessmentSectionTestHelper.GetTestAssessmentLevel());
 
@@ -435,6 +447,8 @@
                     AssertCalculationExists(Path.Combine(folderPath, nestedGroup1.Name, $"{calculation1.Name}.{fileExtension}"));
                     AssertCalculationExists(Path.Combine(folderPath, nestedGroup1.Name, $"{calculation2.Name}.{fileExtension}"));
                     AssertCalculationExists(Path.Combine(folderPath, $"{nestedGroup2.Name} (1)", $"{calculation3.Name}.{fileExtension}"));
+                    AssertCalculationExists(Path.Combine(folderPath, $"{nestedGroup2.Name} (1)", $"{calculation4.Name} (1).{fileExtension}"));
+                    AssertCalculationExists(Path.Combine(folderPath, $"{nestedGroup3.Name} (2)", $"{calculation5.Name}.{fileExtension}"));
                 }
             }
             finally