diff --git a/src/fellchensammlung/tools/admin.py b/src/fellchensammlung/tools/admin.py
index 175409c..569646b 100644
--- a/src/fellchensammlung/tools/admin.py
+++ b/src/fellchensammlung/tools/admin.py
@@ -76,7 +76,7 @@ def deactivate_unchecked_adoption_notices():
 
 def deactivate_404_adoption_notices():
     for adoption_notice in get_active_adoption_notices():
-        if adoption_notice.further_information != "":
+        if adoption_notice.further_information and adoption_notice.further_information != "":
             if is_404(adoption_notice.further_information):
                 adoption_notice.set_closed()
                 logging_msg = f"Automatically set Adoption Notice {adoption_notice.id} closed as link to more information returened 404"