我有兩台 mail server
設定都完全相同 現在出現一個問題
就是 其中一台 發信給 Gmail 會出現問題.
另外一台不會!
兩台是 不同 網域!
所以 是不是 被GOOGLE 封鎖了?還是?
以下是退信 說明

This is the mail system at host mail.localdomain.

I'm sorry to have to inform you that your message could not be delivered to one or more recipients. It's attached below.

For further assistance, please send mail to postmaster.

If you do so, please include this problem report. You can delete your own text from the attached returned message.

               The mail system

kxx.xxx@gmail.com: host gmail-smtp-in.l.google.com[108.177.97.27] said:
550-5.7.1 [220.xxx.xxx.48 7] Our system has detected that this
message is 550-5.7.1 likely unsolicited mail. To reduce the amount of spam
sent to Gmail, 550-5.7.1 this message has been blocked. Please visit
550-5.7.1 https://support.google.com/mail/?p=UnsolicitedMessageError 550
5.7.1 for more information. x61si13415410plb.328 - gsmtp (in reply to end
of DATA command)