SPF is the most effective way to prevent spammers from using your domain name. It's an email authentication standard that allows a domain to publish a public list of which mail servers are permitted to send emails on its behalf. * If you use a device with iOS 15 or earlier, you might not see all of the personalized email addresses that you have set up on a device with iOS 16 or later.SPF stands for Sender Policy Framework. If you don't already own a custom domain, learn how you can purchase an email domain to use with iCloud Mail. If you add someone who’s not part of your Family Sharing group, they need to accept the invitation before they’re added to the domain.

You can share your domain with up to five other people.If you share iCloud+ with your Family Sharing group, you can share your custom domain with your Family sharing group and allow them to create personalized addresses. In iOS 16 or later, you can also share your custom domain with people outside your Family and allow them to create personalized addresses.*.If you don't have any existing email addresses in use with your custom domain, you can create new personalized email addresses after setting up your domain with iCloud Mail.You can also use your personalized email address for Messages, FaceTime, Calendar, to sign in to your device, and more.You can use your personalized email address in the Mail app on any device signed in with your Apple ID and with iCloud Mail turned on, and on /mail.You can use up to five custom domains, with up to three personalized email addresses per domain.If you subscribe to iCloud+, you can use a custom domain that you already own to send and receive email from a personalized email address with iCloud Mail.

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