Sep 21 07:28:51 net2 sendmail[7816]: e8L5Sn907816: ruleset=check_rcpt, arg1=, relay=[202.96.44.19], reject=550 5.0.0 ... Your server spammed us Sep 21 07:28:51 net2 sendmail[7816]: e8L5Sn907816: from=, size=620, class=0, nrcpts=0, proto=ESMTP, daemon=MTA, relay=[202.96.44.19]