diff --git a/phpBB/develop/extensions.php b/phpBB/develop/extensions.php
index 2f7c3d1167..43621f3080 100644
--- a/phpBB/develop/extensions.php
+++ b/phpBB/develop/extensions.php
@@ -37,6 +37,13 @@ function list_extensions()
 	global $phpbb_extension_manager;
 
 	$phpbb_extension_manager->load_extensions();
+	$all = array_keys($phpbb_extension_manager->all_available());
+
+	if (empty($all))
+	{
+		echo "There were no extensions found.\n";
+		exit(3);
+	}
 
 	echo "Enabled:\n";
 	$enabled = array_keys($phpbb_extension_manager->all_enabled());
@@ -49,7 +56,6 @@ function list_extensions()
 	echo "\n";
 
 	echo "Available:\n";
-	$all = array_keys($phpbb_extension_manager->all_available());
 	$purged = array_diff($all, $enabled, $disabled);
 	print_extensions($purged);
 }
diff --git a/phpBB/includes/extension/manager.php b/phpBB/includes/extension/manager.php
index c38f0df32e..dac0e5f947 100644
--- a/phpBB/includes/extension/manager.php
+++ b/phpBB/includes/extension/manager.php
@@ -352,6 +352,10 @@ class phpbb_extension_manager
 	public function all_available()
 	{
 		$available = array();
+		if (!is_dir($this->phpbb_root_path . 'ext/'))
+		{
+			return $available;
+		}
 
 		$iterator = new RecursiveIteratorIterator(
 			new RecursiveDirectoryIterator($this->phpbb_root_path . 'ext/'),