Fatal error: Uncaught Error: Class 'WPMailSMTP\Providers\AuthAbstract' not found in E:\www\web\wp-content\plugins\wp-mail-smtp\src\Providers\Gmail\Auth.php:21 Stack trace: #0 {main} thrown in E:\www\web\wp-content\plugins\wp-mail-smtp\src\Providers\Gmail\Auth.php on line 21