Currently we are implementing to use POP3 / IMAP service for flexibility of mail clients. We are also overlooking on mobiles to be able to access via internet.
We have successfully configured the POP3 / IMAP service and tested already. Now, the main issue when connecting to the SMTP server. I am planning to publicly publish an open STMP relay but with user authentication.
Mail Client (e.g. IMAP) --> Internet --> Firewall ---> Email Server (Relay Host to) --> Microsoft Exchange Online Protection --> External Domain
Right now I was able to test the SMTP service using telnet domain.com 25 it was successfully and having reply from ehlo / helo command. But via on the internet the command or connection reply only with *************** or unrecognized command.
We have already disable SMPT checking or fixup on firewall equipment still no good. I am thinking to use the Microsoft Exchange Online Protection as alternative relay agent.
But how do I configure the Microsoft EOP and mail client on this? Or can you recommend alternative solution. Thank you.
Traveler should be included with your Lotus Domino license.