email client setup

I hope that this would be simple!

Using Outlook, for example, I have entered the user details:

Name
Email Address

Server - pop3
Incoming server - mail.domain.com
SMTP - mail.domain.com

London info
username name.domain (approved format)
password

With smtp, I have it set to authenticate on the same info as pop3.

pop3 incoming seems to work, but smtp doesnt.

I have searched the forums and guides but can find any pointers (I would be surprised if they are not there, somewhere).

what obvious thing have I not/done/wrong!

surprising myself, I seem to hve sorted it out!

All of the credentials were correct.

My issue was reverse DNS. Once I tied the ip address to my domain, it worked.

I did this is my VPS’s HyperVM panel and it worked immediately.