We have a lot of logs that look like below. How can we stop this person from trying to access our imail? Looks like all from one IP 88-212-83-51
08:17 00:46 SMTPD(525f2c350134e960) [88.212.83.51] ERR anthonyltcplanning.com invalid user <[EMAIL PROTECTED] 08:17 00:46 SMTPD(526142580030e965) [64.7.202.222] connect 88.212.83.51 port 12156 08:17 00:46 SMTPD(52603b150126e962) [87.103.181.242] MAIL FROM:<[EMAIL PROTECTED]> 08:17 00:46 SMTPD(526242590030e966) [64.7.202.222] connect 84.108.126.84 port 3069 08:17 00:46 SMTPD(52603b150126e962) [87.103.181.242] RCPT TO: <[EMAIL PROTECTED]> 08:17 00:46 SMTPD(525f2c350134e960) [88.212.83.51] RCPT TO:<[EMAIL PROTECTED]> 08:17 00:46 SMTPD(525f2c350134e960) [88.212.83.51] ERR anthonyltcplanning.com invalid user <[EMAIL PROTECTED] 08:17 00:46 SMTPD(526242590030e966) [84.108.126.84] EHLO YUVAL.4jof61.net 08:17 00:46 SMTPD(52631cfb00e0e967) [64.7.202.222] connect 88.212.83.51 port 12160 08:17 00:46 SMTPD(526242590030e966) [84.108.126.84] MAIL FROM: <[EMAIL PROTECTED]> 08:17 00:46 SMTPD(5263091c00d8e968) [64.7.202.222] connect 87.103.181.242 port 10092 08:17 00:46 SMTPD(526242590030e966) [84.108.126.84] RCPT TO: <[EMAIL PROTECTED]> 08:17 00:46 SMTPD(52631cfc00e0e969) [64.7.202.222] connect 122.162.0.223 port 16527 08:17 00:46 SMTPD(52603b150126e962) [87.103.181.242] D:\IMail\spool\D52603b150126e962.SMD 941 08:17 00:46 SMTPD(5263091c00d8e968) [87.103.181.242] EHLO host-87-103-181-242.pppoe.omsknet.ru 08:17 00:46 SMTPD(52631cfc00e0e969) [122.162.0.223] EHLO 8ypiag.gfceqiz.cox.net 08:17 00:46 SMTPD(526242590030e966) [84.108.126.84] D:\IMail\spool\D526242590030e966.SMD 3388 08:17 00:46 SMTPD(525f2c350134e960) [88.212.83.51] RCPT TO:<[EMAIL PROTECTED]> 08:17 00:46 SMTPD(525f2c350134e960) [88.212.83.51] ERR anthonyltcplanning.com invalid user <[EMAIL PROTECTED]
