diff --git a/lib/Segments/WP.php b/lib/Segments/WP.php
index 116b4defda..c1e882b6f9 100644
--- a/lib/Segments/WP.php
+++ b/lib/Segments/WP.php
@@ -1,10 +1,15 @@
 <?php
 namespace MailPoet\Segments;
-use \MailPoet\Models\Subscriber;
-use \MailPoet\Models\Segment;
-use \MailPoet\Models\SubscriberSegment;
+
+use MailPoet\Models\Subscriber;
+use MailPoet\Models\Segment;
+use MailPoet\Models\SubscriberSegment;
 use MailPoet\Newsletter\Scheduler\Scheduler;
 
+if(!defined('ABSPATH')) exit;
+
+require_once(ABSPATH . 'wp-includes/pluggable.php');
+
 class WP {
   static function synchronizeUser($wp_user_id, $old_wp_user_data = false) {
     $wp_user = \get_userdata($wp_user_id);