In simple terms, a bounce is an email delivery error. These types of errors (i.e. bounces) occur when your email fails to be delivered to your recipient's inbox for a variety of reasons, such as an incorrect recipient email address or a temporary error such as a full mailboxinbox.
Managing these bounces is an important step in keeping your mailing list optimal. If the email that you sent out (or part of your email campaign) bounces, you should consider carefully looking at the email address(es) that bounced and act accordingly. The key is that you want to minimize the number of email errors (i.e. bounces) in your mailing list.
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