SERVER REPLY: 550 Not Found the PTR record of your IP, Check your DNS -PTR ·¹Äڵ带 °Ë»ç¸¦ Çؼ ÇØ´ç IP°¡ È£½ºÆ®¸¦ °Ë»öÇϸøÇÏ´Â °æ¿ì. ISP ¾÷ü¿¡ reverse DNSÀÇ µî·Ï¿äû
REMOTE SERVER RESPONSE : 421 4.3.2 Your IP(192.168.60.12) is filtered and this connection will be closed. 421 Your IP is filtered by IP Rate Control -[½Ã°£´ç Á¢¼Ó Ƚ¼ö Á¦ÇÑ] ¿¡ ÀÇÇؼ Â÷´ÜµÈ ¸ÞÀÏÀÔ
DELIVERY FAILURE: 550 5.3.0 Mail have traversed Too many hops. Reject it. -°ü·Ã ¸Þ¼¼Áö°¡ ³ª¿ÔÀ»°æ¿ì´Â ¸ÞÀÏÀÇ °æ·Î°¡ ÁöÁ¤µÈ Ƚ¼öÀÌ»ó ³Ñ¾úÀ»¶§ ¹ß»ýÇÏ´Â Çö»óÀÔ´Ï´Ù.
Reason:421-: (DNS:NR) http://postmaster.info.aol.com/errors/421dnsnr.html421 SERVICE NOT AVAILABLE -¼ö½ÅÃø ¸ÞÀϼ¹ö¿¡¼ ¹ß¼Û¼¹öÀÇ IP¸¦ Reverse QueryÀ» ÇÏ¿´´Âµ¥ ÀÀ´äÀÌ ¾ø´Â°æ¿ìÀÇ ¸Þ¼¼Áö (ÇØ´ç ISP¾÷ü¿¡°Ô µî·Ï ¿äû)
Reason:421 CCRT 203.233.202.90: Connection refused. Server is busy(RT) -ÇØ´ç ¸ÞÀÏÀº ¼ö½ÅÃø¿¡¼ Server Busy »óÅ·ΠÀÎÇØ, ÀϽÃÀûÀ¸·Î °ÅºÎ
REMOTE SERVER RESPONSE : 451 4.4.2 Bad connection (io timeout) -ÇØ´ç¼¹ö¿¡¼ ÀÀ´äÀÌ ¾ø´Â°æ¿ì
Router: Failed to connect to SMTP host xxx.com because : The remote server is not a known TCP/IP host -ÇØ´ç Àåºñ¿¡ ´ëÇؼ telnet xxx.com 25 ÀÇ ÀÀ´äÀ» ±â´Ù·ÁºÁ¾ß ÇÒ »óȲ
Reason:421 CCRT 203.233.202.90: Connection refused. Server is busy(RT) -Server Busy »óÅ·ΠÀÎÇØ, ÀϽÃÀûÀ¸·Î °ÅºÎÇÑ°ÍÀÔ´Ï´Ù
451 4.3.0 Other or undefined mail system status -Watcher¿Í ¼ö½ÅÃø¿¡¼ Á¤ÀÇÇÏÁö ¾ÊÀº ¸ÞÀÏ ¼¹öÀÇ »óÅ¿¡ ´ëÇÑ ¸®ÅÏ ÄÚµå ¸íÈ®ÇÑ ¿øÀÎÀ» ¾Ë±â°¡ ¾î·Á¿ò (ÇØ´ç °ü¸®ÀÚ¿¡°Ô ¹®ÀÇ)