리턴메시지를 읽어보시면 원인이 적혀 있습니다.
일정 개수 이상의 메일을 보내서 IP를 차단했다는 의미 입니다.
다음쪽에 가보시면 차단된 IP를 조회해 볼수있는 곳이 있을겁니다.

임주현 님이 쓴 글입니다.
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:※ 필수입력정보 ※
:
:▷ 제품버젼 :
:▷ 사용중인 주소(URL) : http://http://mms.wo.tc:8080/mail/
:▷ 문제발생시 메뉴/주소 :
:▷ 문제발생시 에러메세지
: :
:테스트 아이디 : test 비번 : test
:▷ 질문내용
: :
:다음에다 메일을 보내면
:Error Message : 550 5.7.1 Sorry,your access was denied.Your mail server sent too many e-mails.In case that a spammer abuses your mail server for mail relay,you can manage your mail server again.If you are not a system administrator,inform this message to your system
:
:-- You SendMail --
:
: > > Received: from mail.mms.wo.tc (218.123.123.123)
: > > MX_Record = (mail.mms.wo.tc;)
: > > by mms.wo.tc (218.123.123.1) with [Nmail V3.6 20040105(S)]
: > > for from ;
: > > Wed, 09 Nov 2005 16:42:47 +0900
: > > From: =?ks_c_5601-1987?b?v+6/tcDa?=
: > > Subject: d
: > > To:
: > > MIME-Version: 1.0
: > > X-Mailer: SM
: > > Date: Wed, 09 Nov 2005 16:42:47 +0900
: > > Content-Type: text/html; charset=euc-kr
: > > Content-Transfer-Encoding: base64
: > > X-NMailFilter-Result: Clean
: > >
: > > PHN0eWxlPlAge21hcmdpbi10b3A6MnB4O21hcmdpbi1ib3R0b207MnB4O308L3N0
: > > eWxlPmY8aW1nIHNyYz0iaHR0cDovL21tcy53by50Yzo4MDgwL21haWwvTWFpbENv
: > > bmZpcm0vQ29uZmlybS5hc3A/Y29uZmlybUNvZGU9YWRtaW4xNzA2MjAwNTExMDkx
: > > NjQyNDciIHdpZHRoPSIwIiBoZWlnaHQ9IjAiPjwhLS0gLS0+DQo8YnI+DQo8aHRt
: > > bD4NCjxib2R5Pg0KPGJyPg0KPT09PT09PT09PT09PT09PT09PT09PT09PT09PT09
: > > PT09PT09PT09PT09PT09PT0NCjxicj4NCi0gRWFzeSAhIEZhc3QgISBQb3dlcmZ1
: > > bCBObWFpbCBzZXJpZXMhDQo8YnI+DQotIERvd25sb2FkIHNpdGUgPGEgaHJlZj0i
: > > aHR0cDovL3Bhc3Nrb3JlYS5uZXQKIiB0YXJnZXQ9Il9uZXJibGFuayI+aHR0cDov
: > > L3Bhc3Nrb3JlYS5uZXQ8L2E+PGJyPg0KPGJvZHk+DQo8aHRtbD4NCg==
: > >
: > >
: > >
: > >
: > >
: > >
: > >
: > >
:라고뜨고여 핫메일은 무소식...
: