--- a/management/univention-directory-policy/20univention-directory-policy.inst	
+++ a/management/univention-directory-policy/20univention-directory-policy.inst	
@@ -35,7 +35,7 @@ VERSION=1
 . /usr/share/univention-join/joinscripthelper.lib
 joinscript_init
 
-run-parts /usr/lib/univention-directory-policy
+run-parts /usr/lib/univention-directory-policy || die
 
 joinscript_save_current_version
 exit 0