diff --git a/LiamWorkflowDiagnostics/MainWindow.xaml.cs b/LiamWorkflowDiagnostics/MainWindow.xaml.cs
index f9817e6..b29ee17 100644
--- a/LiamWorkflowDiagnostics/MainWindow.xaml.cs
+++ b/LiamWorkflowDiagnostics/MainWindow.xaml.cs
@@ -592,6 +592,8 @@ namespace LiamWorkflowDiagnostics
                 if (string.IsNullOrWhiteSpace(parentPath))
                     throw new InvalidOperationException("Parent Folder Path konnte nicht ermittelt werden.");
                 var ownerSids = ParseIdentifierList(NtfsCreateOwnerSidsTextBox.Text, "Owner SIDs");
+                if (ownerSids.Count == 0)
+                    throw new InvalidOperationException("Owner SIDs: mindestens ein Eintrag ist fuer die Ordneranlage erforderlich.");
 
                 var result = EnsureSuccessfulResultToken(await provider.CreateDataAreaAsync(
                     folderPath,