한메일 발송하면 리턴됩니다.

게시판에서 찾아서 SMTP 인증으로 변경도 해봤는데 똑같네요..

어떻게 해야하는지....

※ 필수입력정보 ※

▷ 제품버젼 : Nmail(Windows) v3.5
▷ 사용중인 주소(URL) : http://www.sscmc.or.kr
▷ 문제발생시 메뉴/주소 :
▷ 문제발생시 에러메세지

Error Message : 554 5.7.1 59.6.149.13: Connection refused. Your IP address is blocked(anti-spam).

-- You SendMail --

>> Received: from 59.6.149.13 (59.6.149.13)
>> by sscmc.or.kr (59.6.149.13) with [Nmail V3.5 20040105(S)]
>> for <****@****> from ;
>> Thu, 28 Sep 2006 15:41:20 +0900
>> From: =?ks_c_5601-1987?b?seiw5rT2?=
>> Subject: 222
>> To: ****@****
>> Cc: ****@****
>> MIME-Version: 1.0
>> X-Mailer: Nmail-3.5 by passkorea.net
>> Date: Thu, 28 Sep 2006 15:41:20 +0900
>> Content-Type: text/html; charset=euc-kr
>> Content-Transfer-Encoding: base64
>>
>> PEhUTUw+DQo8SEVBRD4NCjxNRVRBIE5BTUU9IkdFTkVSQVRPUiIgQ29udGVudD0i
>> TWljcm9zb2Z0IERIVE1MIEVkaXRpbmcgQ29udHJvbCI+DQo8VElUTEU+PC9USVRM
>> RT4NCjwvSEVBRD4NCjxCT0RZPg0KPERJVj48Rk9OVCBmYWNlPbG8uLIgc2l6ZT0y
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>> IGhlaWdodD0iMCI+PCEtLSAtLT4NCjxicj4NCjxodG1sPg0KPGJvZHk+DQo8YnI+
>> DQo9PT09PT09PT09PT09PT09PT09PT09PT09PT09PT09PT09PT09PT09PT09PT09
>> PQ0KPGJyPg0KLSBFYXN5ICEgRmFzdCAhIFBvd2VyZnVsIE5tYWlsIHNlcmllcyEN
>> Cjxicj4NCi0gRG93bmxvYWQgc2l0ZSA8YSBocmVmPSJodHRwOi8vcGFzc2tvcmVh
>> Lm5ldAoiIHRhcmdldD0iX25lcmJsYW5rIj5odHRwOi8vcGFzc2tvcmVhLm5ldDwv
>> YT48YnI+DQo8Ym9keT4NCjxodG1sPg0K

▷ 질문내용
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