diff --git a/servers/slapd/at.c b/servers/slapd/at.c
index 4753d07758..29cc14df25 100644
--- a/servers/slapd/at.c
+++ b/servers/slapd/at.c
@@ -204,7 +204,8 @@ at_destroy( void )
 		ldap_pvt_thread_mutex_destroy(&a->sat_ad_mutex);
 		ldap_attributetype_free((LDAPAttributeType *)a);
 	}
-	ad_destroy(slap_schema.si_at_undefined->sat_ad);
+	if ( slap_schema.si_at_undefined )
+		ad_destroy(slap_schema.si_at_undefined->sat_ad);
 }
 
 static int