请版主帮忙分析这个退信原因是什么？ 谢谢！
我用的是SENDMAIL 邮件服务器，向美国的mail.mydg.come服务器用户发信退回以下信息， 请分析一下是何原因？
-----Original Message-----
From: Mail Delivery Subsystem
[mailto:MAILER-DAEMON@localhost.localdomain]
Sent: Monday, May 30, 2005 6:13 PM
To zhou@tsi-ltd.com
Subject: Returned mail: see transcript for details
The original message was received at Wed, 25 May 2005 17:58:49 +0800
from [211.96.108.131]
----- The following addresses had permanent fatal errors -----
----- Transcript of session follows -----
451 4.4.1 reply: read error from express.webdns.net.
... Deferred: Connection reset by express.webdns.net.
Message could not be delivered for 5 days
Message will be deleted from queue
------------------------------------------------------------
From: "zhou"
To: "Young Wei"
Subject: RE: Greetings from NY!
Date: Wed25 May 2005 18:04:09 +0800
re-send, email got bounce back....
-----Original Message-----
From: zhou [mailto:zhou@tsi-ltd.com]
Sent: Tuesday, May 17, 2005 3:23 PM
To: Young Wei
Subject: FW: Greetings from NY!
-----Original Message-----
From: zhou [mailto:zhou@tsi-ltd.com]
Sent: Thursday, May 12, 2005 12:25 PM
To: Young Wei
Subject: RE: Greetings from NY!
