If I want to offer external access to my Zimbra server with the web client and IMAP I need to open these two ports:
IMAP SSL 993
However, I'm not sure about SMTP. Is it enought to open port 25 or should I also open 587? Can someone please explain.
Finally, client mail application settings.
This is going to sound silly, but in a single server setup am I correct that the incoming and outgoing mail servers are the same, i.e. mail.mydomain.com? I was looking at my personal Apple me.com setup and the servers are different, i.e. mail.me.com and smtp.me.com.
Also, should the connection for outgoing mail use SSL and/ or authentication or neither?