Hello I use ISPconfig v3.0.16 for a long time. Today I found I can't send email from outside network. I can't connect the ispconfig server use telnet mail.mymail.com 25 from outside network but I can connect it in the local network. I have set the DMZ to the ispconfig server. and check the Centos5.3 have no firewall. anyone can give me hits thank you very much !!!