Index: DamTools/LayerOnSlopeTool/trunk/src/Deltares.LayerOnSlopeTool.Importer/CsvImporterLocations.cs
===================================================================
diff -u -r3140 -r3148
--- DamTools/LayerOnSlopeTool/trunk/src/Deltares.LayerOnSlopeTool.Importer/CsvImporterLocations.cs	(.../CsvImporterLocations.cs)	(revision 3140)
+++ DamTools/LayerOnSlopeTool/trunk/src/Deltares.LayerOnSlopeTool.Importer/CsvImporterLocations.cs	(.../CsvImporterLocations.cs)	(revision 3148)
@@ -24,9 +24,10 @@
 using System.IO;
 using System.Linq;
 using System.Threading;
+using Deltares.LayerOnSlopeTool.Data.CsvImporters;
 using LumenWorks.Framework.IO.Csv;
 
-namespace Deltares.LayerOnSlopeTool.Data.CsvImporters
+namespace Deltares.LayerOnSlopeTool.Importer
 {
     /// <summary>
     /// Holds the importer for the locations from csv files
@@ -144,12 +145,18 @@
                      }
                 
                      int colIndexLocationId = CsvReaderUtilities.GetHeaderIndexByString(headers, CsvColumnNames.LocationColumnName);
+                     CheckColumn(colIndexLocationId, fileName, CsvColumnNames.LocationColumnName);
                      int colIndexSurfaceLineId = CsvReaderUtilities.GetHeaderIndexByString(headers, CsvColumnNames.SurfaceLineColumnName);
+                     CheckColumn(colIndexSurfaceLineId, fileName, CsvColumnNames.SurfaceLineColumnName);
                      int colIndexXSoilGeometry2DOrigin = CsvReaderUtilities.GetHeaderIndexByString(headers, CsvColumnNames.XSoilGeometry2DOriginColumnName);
                      int colIndexDikeEmbankmentMaterial = CsvReaderUtilities.GetHeaderIndexByString(headers, CsvColumnNames.DikeEmbankmentMaterialColumnName);
+                     CheckColumn(colIndexDikeEmbankmentMaterial, fileName, CsvColumnNames.DikeEmbankmentMaterialColumnName);
                      int colSoilGeometryName = CsvReaderUtilities.GetHeaderIndexByString(headers, CsvColumnNames.SoilGeometryNameColumnName);
+                     CheckColumn(colSoilGeometryName, fileName, CsvColumnNames.SoilGeometryNameColumnName);
                      int colLayerMaterial = CsvReaderUtilities.GetHeaderIndexByString(headers, CsvColumnNames.LayerMaterialColumnName);
+                     CheckColumn(colLayerMaterial, fileName, CsvColumnNames.LayerMaterialColumnName);
                      int colLayerThickness = CsvReaderUtilities.GetHeaderIndexByString(headers, CsvColumnNames.LayerThicknessColumnName);
+                     CheckColumn(colLayerThickness, fileName, CsvColumnNames.LayerThicknessColumnName);
 
                      var index = 1;
                      while (csv.ReadNextRecord())
@@ -159,7 +166,7 @@
                          try
                          {
                              locationRecord.LocationRecordId = index++;
-                    
+
                              /*
                              * Required columns
                              */
@@ -216,5 +223,14 @@
         {
             get { return errorMessages; }
         }
+
+        private void CheckColumn(int index, string fileName, string fieldName)
+        {
+            if (index < 0)
+            {
+                var csvHeaderFieldError = "The header misses the field: ";
+                throw new ArgumentException(string.Format("{0} : {1} {2}", fileName, csvHeaderFieldError, fieldName));
+            }
+        }
     }
 }