diff --git a/PROMS/DataLoader/DataLoaderSettings.cs b/PROMS/DataLoader/DataLoaderSettings.cs
index 6ab0668c..75028a1a 100644
--- a/PROMS/DataLoader/DataLoaderSettings.cs
+++ b/PROMS/DataLoader/DataLoaderSettings.cs
@@ -294,10 +294,21 @@ namespace DataLoader
 					ErrorPrefix = "";
 				}
 				// ProcedureSetPath = If OnlyThisSet is checked, then has to be non-blank
-				if (OnlyThisSet && (ProcedureSetPath ?? "") == "" || !Directory.Exists(ProcedureSetPath))
+				if (OnlyThisSet)
 				{
-					sb.Append(ErrorPrefix + "Procedure Folder must point to an existing folder\r\n");
-					ErrorPrefix = "";
+					if ((ProcedureSetPath ?? "") == "" || !Directory.Exists(ProcedureSetPath))
+					{
+						sb.Append(ErrorPrefix + "Procedure Folder must point to an existing folder\r\n");
+						ErrorPrefix = "";
+					}
+					else
+					{
+						if (!File.Exists(ProcedureSetPath + @"\set.dbf"))
+						{
+							sb.Append(ErrorPrefix + "Procedure Folder must point to an existing procedure data folder\r\n");
+							ErrorPrefix = "";
+						}
+					}
 				}
 				// BackupFileName = Has to be non-blank
 				if ((BackupFileName ?? "") == "")