diff --git a/adminer/drivers/simpledb.inc.php b/adminer/drivers/simpledb.inc.php
index d2c805dd..63ca4869 100644
--- a/adminer/drivers/simpledb.inc.php
+++ b/adminer/drivers/simpledb.inc.php
@@ -2,10 +2,10 @@
 $drivers["simpledb"] = "SimpleDB";
 
 if (isset($_GET["simpledb"])) {
-	$possible_drivers = array("SimpleXML");
+	$possible_drivers = array("SimpleXML + allow_url_fopen");
 	define("DRIVER", "simpledb");
 
-	if (class_exists('SimpleXMLElement')) {
+	if (class_exists('SimpleXMLElement') && ini_bool('allow_url_fopen')) {
 		class Min_DB {
 			var $extension = "SimpleXML", $server_info = '2009-04-15', $error, $timeout, $next, $affected_rows, $_result;
 
diff --git a/changes.txt b/changes.txt
index b506045f..eb76513a 100644
--- a/changes.txt
+++ b/changes.txt
@@ -2,6 +2,7 @@ Adminer 4.5.1-dev:
 Fix counting selected rows after going back to select page
 PHP <5.3 compatibility even with Elasticsearch enabled
 MariaDB: Support JSON since MariaDB 10.2
+SimpleDB: Document that allow_url_fopen is required
 Malay translation
 
 Adminer 4.5.0 (released 2018-01-24):