Essentially you'll need to configure bindings in IIS for each hostname you want set up in SmarterMail with an HTTPS connection, then run through that process linked above to generate SSL certificates for them. Its pretty straight forward, but please don't hesitate to reach out if you get stuck. 

Thanks Kyle - I have about 50 sites. Since I don't have any Host Headers assigned, they all work. 

Looks like I'll need to add each one (for both port 80 and 443) in the bindings first?

How about "Require Server Name Indication". I have that turned on on a web server that I use Let's Encrypt with.

Hello Dean, you're very welcome. Correct, Lets Encrypt (Certify client) will not request certificates for any domains other than the ones already set up as port 80 (HTTP) bindings in IIS. So once all the HTTP bindings are in place and verified working, you just run the Certify client to generate and verify SSL certificates for them. Certify will also automatically install the port 443 (HTTPS) bindings once verification completes. Server name indication and whether or not you use it largely depends on the server, software environment and configuration, and your average client devices as some will support SNI and others will not. For maximum security you'll want to enable SNI across the board.

Kyle,

  I have a paid installation ticket ( 1A3-24893B82-001C ) in with Tony, ongoing right now,  in which I think your comments above are part/complete solution to the problems we're experiencing.  

Could someone look at that ticket for me and see if this is a good/bad solution?

Many thanks,

Stephen

Stephen Smith 

I have done my server with multiple ssl configuration. Purchase any SSL vendor SNI certification, The SNI certificate will be very usefull for multiple domain. I have hosted all my sites different server and mail service in different server so main site ssl not help for hosting mail service. ( Lets Encrypt)

For example some of the SSL vendor provide , 5 , 10, 15  etc domains bulk purchase option and implement in IIS