THANKS to Kyle from ST for these instructions...

Deployment of autodiscover for IMAP/POP/SMTP/etc is pretty straight forward, and only requires a few A and SRV records in DNS. Reach out to us (MBF) if help is needed with adding these or see this article:

https://www.mailenable.com/kb/content/article.asp?ID=ME020681

Once those records have been deployed the vast majority of email clients and mobile devices should be able to find the SRV records and auto-configuring the accounts using those hostnames and port settings. However, some devices/email clients will not leverage these SRV records and elect to default to hostnames like imap.customer-domain.com, pop.customer-domain.com, smtp.customer-domain.com, etc.

On the EAS/EWS/MAPI side autodiscover is required, and can introduce sync issues when not properly configured. ST has a document on getting autodiscover set up for those protocols:

https://portal.smartertools.com/kb/a3179/set-up-autodiscover-for-smartermail.aspx

When deployed correctly these statements should be true:

1. https://mail.customer-domain.com should be reachable without security warnings from a browser.
2. https://autodiscover.customer-domain.com should be reachable without security warnings from a browser.
3. SRV record should be reachable from DNS on the client PC, and should point to mail.customer-domain.com on port 443.

If any of those addresses above redirect to another domain name, this will result in a security warning occurring in the background during account set up and this will fail the account discovery process. As such, a wildcard SSL becomes required in order to secure the web interface for all possible autodiscover hostnames and to secure IMAP/POP/etc in the same manner. For this, ST recommends Lets Encrypt:

https://portal.smartertools.com/kb/a3466/securing-smartermail-with-lets-encrypt.aspx

Once deployed you'll have a single certificate in IIS which covers all possible hostnames and a matching PFX for use to secure the SM ports.