stmp无法使用

无法发信，提示:
object(WP_Error)#6174 (2) { [\"errors\"]=> array(1) { [\"wp_mail_failed\"]=> array(1) { [0]=> string(35) \"SMTP Error: Could not authenticate.\" } } [\"error_data\"]=> array(1) { [\"wp_mail_failed\"]=> array(6) { [\"to\"]=> array(1) { [0]=> string(16) \"331969102@qq.com\" } [\"subject\"]=> string(6) \"你好\" [\"message\"]=> string(6) \"你好\" [\"headers\"]=> array(0) { } [\"attachments\"]=> array(0) { } [\"phpmailer_exception_code\"]=> int(0) } } }