Mahayudin Mohd Hashim wrote: > abhishek singh wrote: >> i have never opened telnet ok , my xinetd service is >> off so there is no telnet service , i m doing telnet >> to outside to 25 port on my mail server and there is >> proper smtp authentication enabled on server , the >> problem is anyuser (non-existing) with my domain can >> send mail to my real domain users. >> below is example........ >> > > Check this and do accordingly ... > > http://www.sendmail.org/faq/section3.html#3.27 > http://www.sendmail.org/tips/relaying.html > > hope this help! > It does not. He does not have a relay problem. He wants to reject mails that have sender addresses claiming to be from his domain and not only that, they are also forged (non-existent).