Hi, My mail log is giving me these type of messages below. Looks like some guy or group of peole is using my smtp server as a relay machine. Fortunately my smtp rules are forbidding it, i think. But how do i stop all these messages in the mail log? The from is not frommy domain and looks like they can access my smtp and send email... I am using suse 7.3 and it is outdated and still working on my new 9.2 box, but i am curious what happened and how to resolve the problem. thanks henry ], reject=550 5.7.1 ... Relaying denied Mar 31 09:12:22 main sendmail[20762]: j2VFCEA20762: from=, size=0, class=0, nrcpts=0, proto=SMTP, daemon=MTA, relay=219-81-229-104.static.tfn.net.tw [219.81.229.104] Mar 31 09:12:22 main sendmail[20765]: j2VFCIA20765: from=, size=0, class=0, nrcpts=0, proto=ESMTP, daemon=MTA, relay=61-31-138-39.dynamic.tfn.net.tw [61.31.138.39] Mar 31 09:12:25 main sendmail[20767]: j2VFCNA20767: ruleset=check_rcpt, arg1=, relay=61-31-138-39.dynamic.tfn.net.tw [61.31.138.39], reject=550 5.7.1 ... Relaying denied Mar 31 09:12:25 main sendmail[20766]: j2VFCIA20766: ruleset=check_rcpt, arg1=, relay=219-81-238-110.static.tfn.net.tw [219.81.238.110], reject=550 5.7.1 ... Relaying denied Mar 31 09:12:25 main sendmail[20766]: j2VFCIA20766: from=, size=0, class=0, nrcpts=0, proto=SMTP, daemon=MTA, relay=219-81-238-110.static.tfn.net.tw [219.81.238.110] Mar 31 09:12:28 main sendmail[20767]: j2VFCNA20767: from=, size=0, class=0, nrcpts=0, proto=ESMTP, daemon=MTA, relay=61-31-138-39.dynamic.tfn.net.tw [61.31.138.39] Mar 31 09:12:28 main sendmail[19729]: j2UNB0127150: to=, delay=16:01:28, xdelay=00:00:31, mailer=esmtp, pri=2677160, relay=mx.pchome.com.tw. [211.20.188.150], dsn=4.0.0, stat=Deferred: 440 Error: Wrong recipients Mar 31 09:12:31 main sendmail[20769]: j2VFCTA20769: ruleset=check_rcpt, arg1=, relay=61-31-138-39.dynamic.tfn.net.tw [61.31.138.39], reject=550 5.7.1 ... Relaying denied Mar 31 09:12:32 main sendmail[20769]: j2VFCTA20769: from=, size=0, class=0, nrcpts=0, proto=ESMTP, daemon=MTA, relay=61-31-138-39.dynamic.tfn.net.tw [61.31.138.39] Mar 31 09:12:35 main sendmail[20770]: j2VFCXA20770: ruleset=check_rcpt, arg1=, relay=61-31-138-39.dynamic.tfn.net.tw [61.31.138.39], reject=550 5.7.1 ... Relaying denied Mar 31 09:12:36 main sendmail[20770]: j2VFCXA20770: from=, size=0, class=0, nrcpts=0, proto=ESMTP, daemon=MTA, relay=61-31-138-39.dynamic.tfn.net.tw [61.31.138.39] Mar 31 09:12:39 main sendmail[20772]: j2VFCbA20772: ruleset=check_rcpt, arg1=, relay=61-31-138-39.dynamic.tfn.net.tw [61.31.138.39], reject=550 5.7.1 ... Relaying denied Mar 31 09:12:39 main sendmail[19729]: j2UNB0127150: to=, delay=16:01:39, xdelay=00:00:42, mailer=esmtp, pri=2677160, relay=mx.pchome.com.tw. [211.20.188.150], dsn=4.0.0, stat=Deferred: 440 Error: Wrong recipients Mar 31 09:12:40 main sendmail[20772]: j2VFCbA20772: from=, size=0, class=0, nrcpts=0, proto=ESMTP, daemon=MTA, relay=61-31-138-39.dynamic.tfn.net.tw [61.31.138.39] Mar 31 09:12:43 main sendmail[20774]: j2VFCfA20774: ruleset=check_rcpt, arg1=, relay=61-31-138-39.dynamic.tfn.net.tw [61.31.138.39], reject=550 5.7.1 ... Relaying denied Mar 31 09:12:44 main sendmail[20774]: j2VFCfA20774: from=, size=0, class=0, nrcpts=0, proto=ESMTP, daemon=MTA, relay=61-31-138-39.dynamic.tfn.net.tw [61.31.138.39] Mar 31 09:12:46 main sendmail[20777]: j2VFCjA20777: ruleset=check_rcpt, arg1=, relay=61-31-138-39.dynamic.tfn.net.tw [61.31.138.39], reject=550 5.7.1 ... Relaying denied Mar 31 09:12:46 main sendmail[20776]: j2VFCjA20776: ruleset=check_rcpt, arg1=, relay=219-81-231-102.static.tfn.net.tw [219.81.231.102], reject=550 5.7.1 ... Relaying denied Mar 31 09:12:47 main sendmail[20776]: j2VFCjA20776: ruleset=check_rcpt, arg1=, relay=219-81-231-102.static.tfn.net.tw [219.81.231.102], reject=550 5.7.1 ... Relaying denied Mar 31 09:12:47 main sendmail[20776]: j2VFCjA20776: ruleset=check_rcpt, arg1=, relay=219-81-231-102.static.tfn.net.tw [219.81.231.102], reject=550 5.7.1 ... Relaying denied Mar 31 09:12:47 main sendmail[20777]: j2VFCjA20777: from=, size=0, class=0, nrcpts=0, proto=ESMTP, daemon=MTA, relay=61-31-138-39.dynamic.tfn.net.tw [61.31.138.39] Mar 31 09:12:48 main sendmail[20776]: j2VFCjA20776: ruleset=check_rcpt, arg1=, relay=219-81-231-102.static.tfn.net.tw [219.81.231.102], reject=550 5.7.1 ... Relaying denied Mar 31 09:12:48 main sendmail[20776]: j2VFCjA20776: ruleset=check_rcpt, arg1=, relay=219-81-231-102.static.tfn.net.tw [219.81.231.102], reject=550 5.7.1 ... Relaying denied Mar 31 09:12:49 main sendmail[20776]: j2VFCjA20776: ruleset=check_rcpt, arg1=<19720319@yahoo.com.tw>, relay=219-81-231-102.static.tfn.net.tw [219.81.231.102], reject=550 5.7.1 <19720319@yahoo.com.tw>... Relaying denied Mar 31 09:12:49 main sendmail[20778]: j2VFCmA20778: ruleset=check_rcpt, arg1=, relay=61-31-138-39.dynamic.tfn.net.tw [61.31.138.39], reject=550 5.7.1 ... Relaying denied