SMTP Configurations For iCloud Custom Domain Email

Hello JingerTea,

I have been able to set up Apple Mail on MacOS to send messages from my custom email domain. Here's what I did:

• Enter the custom email address for the Email Address under the Account Information tab.
• Enter the standard iCloud information for the Outgoing Mail Server (SMTP) under the Server Settings tab. This configuration is described in Mail server settings for iCloud email clients - Apple Support. It's worth noting that you should use your iCloud email address here to authenticate, not your custom domain address.

You should be able to use this technique for other email client applications too.

I want to add that although my technique "works", it is not quite 100% working properly. The email does not include a DKIM signature which is used to help identify spam. The reason is that MacOS Apple Mail is using the domain email address instead of the iCloud address in the SMTP "mail from" protocol line.

So if you use this method, some email recipient systems may flag your messages as spam.

If anyone is still interested in this topic, I would like to add that I tried sending email with a plain iCloud email user on iOS 15. It presented the option to send with a custom email address but when I did so the email did not include a DKIM signature. So I suspect that this problem has to do with something on the iCloud back-end and not some particular SMTP configuration setting.