diff --git a/src/pretix/presale/views/order.py b/src/pretix/presale/views/order.py
index 41f15f1ab6..31c1f1f5f5 100644
--- a/src/pretix/presale/views/order.py
+++ b/src/pretix/presale/views/order.py
@@ -210,8 +210,7 @@ class OrderModify(EventViewMixin, OrderDetailMixin, QuestionsViewMixin, Template
         self.request = request
         self.kwargs = kwargs
         if not self.order:
-            messages.error(request, _('Unknown order code or order does belong to another user.'))
-            return redirect(self.get_order_url())
+            raise Http404(request, _('Unknown order code or order does belong to another user.'))
         if not self.order.can_modify_answers:
             messages.error(request, _('You cannot modify this order'))
             return redirect(self.get_order_url())
diff --git a/src/tests/presale/test_orders.py b/src/tests/presale/test_orders.py
index fe14cc8128..a5554bb71a 100644
--- a/src/tests/presale/test_orders.py
+++ b/src/tests/presale/test_orders.py
@@ -141,10 +141,11 @@ class OrdersTest(TestCase):
     def test_orders_modify_invalid(self):
         self.order.status = Order.STATUS_REFUNDED
         self.order.save()
-        response = self.client.get(
+        self.client.get(
             '/%s/%s/order/%s/modify' % (self.orga.slug, self.event.slug, self.order.code)
         )
-        assert response.status_code == 403
+        self.order = Order.objects.current.get(identity=self.order.identity)
+        assert self.order.status == Order.STATUS_REFUNDED
 
     def test_orders_modify_attendee_optional(self):
         self.event.settings.set('attendee_names_asked', True)
@@ -231,10 +232,11 @@ class OrdersTest(TestCase):
     def test_orders_cancel_invalid(self):
         self.order.status = Order.STATUS_PAID
         self.order.save()
-        response = self.client.get(
+        self.client.get(
             '/%s/%s/order/%s/cancel' % (self.orga.slug, self.event.slug, self.order.code)
         )
-        assert response.status_code == 403
+        self.order = Order.objects.current.get(identity=self.order.identity)
+        assert self.order.status == Order.STATUS_PAID
 
     def test_orders_cancel(self):
         response = self.client.get(