smtp 인증 테스트 방법이다. 실패된 경우 # telnet smtp.office365.com 25 Connected to test-com.mail.protection.outlook.com (133.144.133.144). Escape character is '^]'. 220 smtp.office365.com Microsoft ESMTP MAIL Service ready at Tue, 14 Feb 2017 05:38:59 +0000 helo 250 HK2PR04CA0040.outlook.office365.com Hello [111.122.133.144] mail from:test@microsoft.com 530 5.7.57 SMTP; Client was not authenticated to send an..