안녕하세요. 이현민이라고 합니다.
 다른 곳에서 제 서버로 메일을 보내면
보낸 곳에 리턴 되어 옵니다. 에러 메세지는 다음과 같습니다.
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The original message was received at Tue, 18 Jul 2000 14:28:27 +0900
from www10.hanmail.net [211.32.117.30]
  ----- The following addresses had permanent fatal errors -----
<myid at csn.ne.kr>
 ----- Transcript of session follows -----
<myid at csn.ne.kr>... Deferred: Connection refused by csn.ne.kr.
Message could not be delivered for 6 hours
Message will be deleted from queue
   
Reporting-MTA: dns; s-mail12.hanmail.net
Arrival-Date: Tue, 18 Jul 2000 14:28:27 +0900
 Final-Recipient: RFC822; myid at csn.ne.kr Action: failed
Status: 4.4.7
Remote-MTA: DNS; csn.ne.kr
Last-Attempt-Date: Tue, 18 Jul 2000 20:28:51 +0900
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 원인 무었이지 궁금합니다.
고수님 부탁합니다.
 참고로 서버에서 제한테 보낸 편지는 받을 수 있습니다.
그런에 다른 곳에서 보낸 편지는 받을 수 없습니다.
 밑에는 테스트 결과 입니다.
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$ telnet localhost 25
Trying 127.0.0.1...
Connected to localhost.csn.ne.kr.
Escape character is '^]'.
220 ns1.csn.ne.kr ESMTP Sendmail 8.9.3/8.9.3; Wed, 19 Jul 2000
12:13:25 +0900
mail from : root at csn.ne.kr 250 myid at csn.ne.kr... Sender ok
rctp to : myid at csn.ne.kr 250 myid at csn.ne.kr... Recipient ok
data 잘 되야 될텐데.
354 Enter mail, end with "." on a line by itself
quit
.
250 MAA00891 Message accepted for delivery
quit
221 ns1.csn.ne.kr closing connection
Connection closed by foreign host.
You have new mail in /var/spool/mail/myid
  $ telnet localhost 110
Trying 127.0.0.1...
Connected to localhost.csn.ne.kr.
Escape character is '^]'.
+OK POP3 localhost.localdomain v7.64 server ready
user myid
+OK User name accepted, password please
pass *********
+OK Mailbox open, 1 messages
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