diff --git a/ChatController/HauptKlassen/Chat.cs b/ChatController/HauptKlassen/Chat.cs
index 17d55e3..1596640 100644
--- a/ChatController/HauptKlassen/Chat.cs
+++ b/ChatController/HauptKlassen/Chat.cs
@@ -87,13 +87,14 @@ namespace ChatController.HauptKlassen
                     Kontaktliste.Add(new KontaktlistBuilder(value.Name, AvatarToImageSourceConverter(value.Avatar),
                         message, timeformated, value.Oid, null));
 
+                    if(lastMS != null && lastMS.Timestamp != null && lastMS.Timestamp.Date != null) { 
+                        TimeSpan span = (DateTime.Parse(lastMS.Timestamp.Date) - new DateTime(1970, 1, 1, 0, 0, 0, 0, DateTimeKind.Utc));
+                        long unixTime = System.Convert.ToInt64(span.TotalSeconds);
 
-                    TimeSpan span = (DateTime.Parse(lastMS.Timestamp.Date) - new DateTime(1970, 1, 1, 0, 0, 0, 0, DateTimeKind.Utc));
-                    long unixTime = System.Convert.ToInt64(span.TotalSeconds);
-
-                    if (lastTimeStamp < unixTime)
-                    {
-                        lastTimeStamp = unixTime;
+                        if (lastTimeStamp < unixTime)
+                        {
+                            lastTimeStamp = unixTime;
+                        }
                     }
                 }
             }
@@ -683,12 +684,14 @@ namespace ChatController.HauptKlassen
                     Kontakt.Add(new KontaktlistBuilder(value.Name, AvatarToImageSourceConverter(value.Avatar),
                         message, timeformated, value.Oid, null));
 
-                    TimeSpan span = (DateTime.Parse(lastMS.Timestamp.Date) - new DateTime(1970, 1, 1, 0, 0, 0, 0, DateTimeKind.Utc));
-                    long unixTime = System.Convert.ToInt64(span.TotalSeconds);
+                    if (lastMS != null && lastMS.Timestamp != null && lastMS.Timestamp.Date != null) { 
+                        TimeSpan span = (DateTime.Parse(lastMS.Timestamp.Date) - new DateTime(1970, 1, 1, 0, 0, 0, 0, DateTimeKind.Utc));
+                        long unixTime = System.Convert.ToInt64(span.TotalSeconds);
 
-                    if (lastTimeStamp < unixTime)
-                    {
-                        lastTimeStamp = unixTime;
+                        if (lastTimeStamp < unixTime)
+                        {
+                            lastTimeStamp = unixTime;
+                        }
                     }
 
                 }
diff --git a/ChatController/LoginControl.xaml.cs b/ChatController/LoginControl.xaml.cs
index e2f7026..cb3fc24 100644
--- a/ChatController/LoginControl.xaml.cs
+++ b/ChatController/LoginControl.xaml.cs
@@ -114,7 +114,7 @@ namespace ChatController
             }
             catch (Exception exception)
             {
-                MessageBox.Show("Fehler:"+exception.Message, "Fehler", MessageBoxButton.OK, MessageBoxImage.Error);
+                MessageBox.Show("Fehler: " + exception.Message, "Fehler", MessageBoxButton.OK, MessageBoxImage.Error);
                 Cursor = Cursors.Arrow;
             }
         }