现在我不能发邮件到一家公司的邮箱了？请帮忙分析一下问题出在哪里？

zzlan

The attached message had transient non-fatal delivery errors<br>
<br>
THIS IS A WARNING MESSAGE ONLY - YOU DO NOT NEED TO RESEND YOUR MESSAGE!<br>
<br>
This server is configured to automatically retry delivery at configured<br>
intervals. Subsequent attempts to deliver this message are pending.<br>
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Failed address: por@tkkgroup.com<br>
<br>
--- Session Transcript ---<br>Parsing Message <D:\MDAEMON\Remoteq\pd50000532794.msg><br>From: chunlin_wu@sunjex.com<br>To: por@tkkgroup.com<br>Subject:<br>Message-ID: <014901c48fe8$2c38a170$2301a8c0@sjinformation><br>MX-record resolution of [tkkgroup.com] in progress (DNS Server: 202.96.209.5)...<br>P=010 D=tkkgroup.com TTL=(1384) MX=[mail.tkkgroup.com] {203.144.243.34}<br>Attempting MX: P=010 D=tkkgroup.com TTL=(1384) MX=[mail.tkkgroup.com] {203.144.243.34}<br>Attempting SMTP connection to [203.144.243.34 : 25]<br>Waiting for socket connection...<br>Socket connection established (192.168.3.229 : 2492 -> 203.144.243.34 : 25)<br>Waiting for protocol initiation...<br>30 second wait for protocol timeout exceeded.<br>This message is 63 minutes old; it has 0 minutes left in this queue<br>Primary queue lifetime exceeded; message placed in retry queue<br>
--- End Transcript ---<br>
: Message contains [1] file attachments<br>