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The "Confirmation request" is an automated email sent to pending recipients so that they can confirm their intent to subscribe to the list. It's also referred to as the "Subscription confirmation request message" in other areas of our documentation.
Why
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use "confirmed opt-in"
Sending prospective new subscribers to your list a request to confirm their intent to subscribe is an email marketing best practice. In fact, it. It's called double opt-in or confirmed opt-in. It's the only positive way to prevent invalid email addresses and spamtraps from being added to your recipients database as subscribers, since only humans actually interested in receiving messages from you will click on the confirmation link.
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