550 SPF check failed
退信内容：550 SPF check failed. http://service.mail.qq.com/c…
550 Domain may not exist or DNS check failed [NX9WKUWGGZoEdpKuMBJbEmXcZnp1+GoEt62NhQ65bRw2iEld1x+go68= IP: xx.xx.xx.xx]
退信内容：550 Domain may not exist or DNS check failed [NX9W…
550 5.7.1 xxx@xxx.xx may not send mail to
退信内容：550 5.7.1 xxx@xxx.xx may not send mail to <xxx@…
550 Service unavailable; Client Host [xx.xx.xx.xx] blocked using Trend Micro RBL+
退信内容： 550 Service unavailable; Client Host [xx.xx.xx.xx…
550 5.7.1 Recipient unknow<…@...>
退信内容：550 5.7.1 Recipient unknow<…@…> 退信原因：①…
550 Requested action not taken：Invalid IP
退信内容：550 Requested action not taken：Invalid IP<xx.xx…