What is the name of the domain?
What is the error message?
电子邮件将不会送达，未找到 SMTP 服务器
What is the issue you’re encountering
未找到 SMTP 服务器
It sounds like you may be using the wrong SMTP server host name for your email provider, such as for example incorrectly trying to connect to e.g. “mail.example.com”, instead of e.g. “smtp.example.com”.
What does your email provider have to say about the problem?