php - 如何使用 PHP 退回电子邮件

Question

我正在通过一个 PHP 脚本传输所有电子邮件，该脚本根据有效地址的数据库检查收件人地址。如果存在，脚本的其余部分将处理它。但是，如果它不存在，我该如何退回电子邮件，就像我没有脚本时服务器的退回方式一样？谢谢!

Answer 1

邮件是通过 smtp 协议(protocol)接收的，在你的情况下，我还假设有一些服务在端口 25 上运行，它会监听来自外部域的邮件请求。

有多种方式可以退回邮件

->bounce at smtp level itself, as in when u get the recipient list, check f or the id existance and if does-not exists give a 4xx response. The bouncemai l would then be generated by the senders domain automatically.

-> if you have accepted the mail from the domain say gmail.com then u will have to make a new connection to gmail with your bouncemessage, this is same as sending a new mail from your server to gmail.com.