Accessing Email

[JimmydIT]

We have on-premise exchange 2019.  There is no secure gateway application for SM that I have found.

Are you using a web application proxy (WAP) published to the internet for ActiveSync that is configured to communicate with Exchange?

Are there other options?  I see how to set up profiles so that when a user enrolls it has information preconfigured.

[PhilipDAth]

How does SMTP get to the server at the moment?  IP address or port NATed through to it?  If so, use the same approach and NAT tcp/443 through to it.

Otherwise, you could deploy a reverse proxy.  I like using HAProxy, but you can use whatever is your favourite.

None of this has much to do with Systems Manager ...