Autodiscovery enables your users to easily set up Outlook with just an email address and password. To enable autodiscovery, you must create an SRV record in your domain’s DNS with the following settings:

Service: _autodiscover
Protocol: _tcp
Priority: 0
Weight: 100
Port: 443
Target: secure.greatmail.com

If your DNS requires editing the zone file directly, please contact Greatmail support for the proper syntax.