Mail Delivery

Mail Delivery mail delivery system是什么意思 mail delivery subsystem是什么意思啊? Mail delivery failed:returning message to sender 英语翻译Mail Delivery System》Undelivered Mail Returned to Sender This message was created automatically by mail delivery soft Delivery 英语翻译发件人："Mail Delivery System" [添加到地址簿] [拒收] [垃圾举报] 日期：2006- 向德国发信后收到一封主题为Mail delivery failed:returning message to sende 英语翻译Mail Delivery Subsystem 致 我 更多选项 12:16 (6分钟前) This is an People call this mail service Rural Free Delivery.(变为被动语态) 发了邮件后收到"Mail Delivery System"发过来的英文邮件,