Intranet SMTP transmission failure curve saving the nation

Many email service providers do not support emails sent from the IP address that does not verify the SMTP domain name. This problem exists in the company's email sending system. After the test, we had to send emails through the relay of the company email server.

Intranet MIS server: M1

Internet Mail Relay host: S1

On M1, the SMTP virtual server in IIS sets the Relay host to mail.company.com.cn, the outbound security settings to common verification: services@company.com.cn, fill in the actual password

Enable relay on S1.