diff --git a/BeWo/View/Detail/MandatorView.xaml.cs b/BeWo/View/Detail/MandatorView.xaml.cs
index e2811ea29..eeb61eeca 100644
--- a/BeWo/View/Detail/MandatorView.xaml.cs
+++ b/BeWo/View/Detail/MandatorView.xaml.cs
@@ -27,7 +27,11 @@ namespace BeWo.View.Detail
             if (BeWoApp.LoggedOnUser.HasRight(BS.Shared.UserRightType.ChatAdminSettings))
             {
                 var url = ServiceFacade.DoOperationsServiceSync(s => s.GetOwnChatSettingsUrl());
-                HyperlinkOwnChatSettings.NavigateUri = new Uri(url);
+                if (!String.IsNullOrEmpty(url))
+                {
+                    HyperlinkOwnChatSettings.NavigateUri = new Uri(url);
+                }
+                
                 //HyperlinkOwnChatSettings.Inlines.Add("testtestestt");
                 //HyperlinkOwnChatSettings.Text
             }