I'm a newbie here in EE. I am the Domino administrator for my company. My corporate email is using Lotus Domino 6.5.1. In between the server and the internet, I have 2 boxes of mail firewall (but there is a router and firewall as well that i think is not worth to be mentioned). Recently, I received a number of complaints. There are senders that could not sent an email to my corporate email. They keep on receiving a 4.4.7 error code (I assumed they are using Exchange). Normally, all I need to do is check the Message History on the MXtreme to see the error message. But this time, strange things happened. There was no history of mail that coming from their domain!!!
After that, I ask them to resend an email to my corporate email address, and Cc to my gmail. I received the mail on my gmail but not the other one. Now I'm puzzled of what is going on.
I did a telnet test. I telnet to my mail firewall, use the helo, mail from, rcpt to, subject, data command. The mail can be sent without any issue.
(Because of I'm a newbie here, I'm not too sure about revealing a real information on the domain, ip address, etc is legal. I knew that some of the free accessed forum forbid the user from revealing the real information. Please let me know if EE allow those information to be posted here. Then I will published those information. )
Fyi, there was no changes made on the mail server, dns record, or ISP.
Please enlighten me on this. Your cooperation is highly appreciated. Thanks.