diff --git a/Components/Utils/BExIS.Utils.Data/Upload/UploadHelper.cs b/Components/Utils/BExIS.Utils.Data/Upload/UploadHelper.cs
index 3701f3a7b..2117409a1 100644
--- a/Components/Utils/BExIS.Utils.Data/Upload/UploadHelper.cs
+++ b/Components/Utils/BExIS.Utils.Data/Upload/UploadHelper.cs
@@ -467,11 +467,7 @@ public bool IsUnique(long datasetId, string ext, string filename, string filepat
                             // 2 [2][Javad] = 2Javad
                             foreach (List<string> l in tempList)
                             {
-                                string tempString = "";
-                                foreach (string s in l)
-                                {
-                                    tempString += s;
-                                }
+                                string tempString = String.Join("_", l);
                                 if (!String.IsNullOrEmpty(tempString)) primaryValuesAsOneString.Add(tempString);
                             }