diff --git a/openslides/agenda/models.py b/openslides/agenda/models.py
index cd67de1a6..d887d553c 100644
--- a/openslides/agenda/models.py
+++ b/openslides/agenda/models.py
@@ -52,7 +52,14 @@ class Item(MPTTModel, SlideMixin):
         """
         return the object, of which the item points.
         """
-        return get_slide_from_sid(self.related_sid, True)
+        object = get_slide_from_sid(self.related_sid, element=True)
+        if object is None:
+            self.title = 'Item for deleted slide: %s' % self.related_sid
+            self.related_sid = None
+            self.save()
+            return self
+        else:
+            return object
 
     def get_related_type(self):
         """
diff --git a/openslides/agenda/tests.py b/openslides/agenda/tests.py
index 0906eaef2..ca56e009d 100644
--- a/openslides/agenda/tests.py
+++ b/openslides/agenda/tests.py
@@ -15,9 +15,9 @@ from django.test.client import Client
 from django.contrib.auth.models import User
 from django.db.models.query import EmptyQuerySet
 
-from projector.api import get_active_slide
+from openslides.projector.api import get_active_slide
 
-from agenda.models import Item
+from openslides.agenda.models import Item
 
 class ItemTest(TestCase):
     def setUp(self):
@@ -60,6 +60,10 @@ class ItemTest(TestCase):
                 self.assertEqual(initial['parent'], 0)
             self.assertEqual(initial['weight'], item.weight)
 
+    def testRelated_sid(self):
+        self.item1.related_sid = 'foobar'
+        self.assertFalse(self.item1.get_related_slide() is None)
+
 
 class ViewTest(TestCase):
     def setUp(self):