Sending mail to certain domains will result in a return message: 601 attempts to send mail to the following IP: xxx.xxx.xxx.xxx ', DNS, SMTP, firewall settings have been confirmed to be normal, but the interface must be managed on Smart In Mail: "Gateway / Failover" establishes a group of gateways through which he can send mail smoothly. The gateway setting is another set of MAIL software in the same environment of our company, so there is no problem. I think this is a problem with Smartmail. Is there a solution?

This question has been created for ticketing support. Three months have passed, and the current support staff cannot resolve this issue, nor can I transfer it to the RD developer to find this issue.