Set a custom domain for the webmail
If you're a company or a reseller, you may want your users to access the webmail from a different address than postale.io/webmail. Here's how to do that.
Add a CNAME record
Connect to your domain registrar interface and add this CNAME record in the DNS zone
(replace yourdomain.com with your domain name).
Host Value webmail.yourdomain.com webmail.postale.io
That's it. Once the new record has propagated, you'll be able to access the webmail from webmail.yourdomain.com.
Important: the webmail is SSL encrypted for better security (https). For this reason, when you access it via webmail.yourdomain.com, the address shown in the browser is changed to webmail.postale.io.