ggalguli at lycos.co.kr(vow17 at hotmail.com)에서 clean at kor-cleanzone.com 으로 
메일을 
보내면 메일이 안가고 오류메일이 ggalguli at lycos.co.kr(vow17 at hotmail.com)
로 되돌아와요.. 아래같은 메세지로요.
clean at kor-cleanzone.com 으로 편지보내기는 되는데..
메일받는것은 안되는것 같아요... 
뭐가 잘못된것인지 모르겠어요..알려주세요..
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[ggalguli at lycos.co.kr ---> clean at kor-cleanzone.com ] 메일보냈을때 오류
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The original message was received at Tue, 19 Nov 2002 14:46:28 +0900 
(KST)
from [172.22.11.153]

----- The following addresses had permanent fatal errors -----
<clean at kor-cleanzone.com>
(reason: 550 5.7.1 <clean at kor-cleanzone.com>... Relaying denied. IP name 
lookup failed [211.51.63.171])

----- Transcript of session follows -----
... while talking to kor-cleanzone.com.:
>>> RCPT To:<clean at kor-cleanzone.com>
<<< 550 5.7.1 <clean at kor-cleanzone.com>... Relaying denied. IP name 
lookup failed [211.51.63.171]
550 5.1.1 <clean at kor-cleanzone.com>... User unknown
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[vow17 at hotmail.com ---> clean at kor-cleanzone.com ] 메일보냈을때 오류
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This is an automatically generated Delivery Status Notification.

Delivery to the following recipients failed.

       clean at kor-cleanzone.com
 
Reporting-MTA: dns;hotmail.com
Received-From-MTA: dns;mail.hotmail.com
Arrival-Date: Mon, 18 Nov 2002 21:46:32 -0800

Final-Recipient: rfc822;clean at kor-cleanzone.com
Action: failed
Status: 5.7.1
Diagnostic-Code: smtp;550 5.7.1 <clean at kor-cleanzone.com>... Relaying 
denied. 
Proper authentication required.
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