After restart of my EC2 Host (CentOS ISPConfig 3) I found sendmail was only listening on localhost:25 ... I couldn't send mail until I restarted sendmail... I now can send via TLS, but standard SMTP was not working. I edited DAEMON_OPTIONS in sendmail.mc and restarted sendmail and it now listens on 25, but in the log I'm still seeing the message: did not issue MAIL/EXPN/VRFY/ETRN during connection to Daemon0 I'm also seeing some Relaying denied messages for incoming mail. Any ideas? p.s. incidentally my EC2 host went zombie after failing to lease a DHCP address.