Bounce is the percentage of email messages that failed to send. In email marketing, it is acceptable to divide bounces into two gradations depending on the reason the email bounced.
- Hard bounces
- This group includes the following reasons why email addresses may bounce:
- "The domain name doesn't exist."This means that it is impossible to deliver the email to the recipient's email address.
- "The email address doesn't exist." This means that the delivery failed because there is no such email address on the current domain.
- "Spam by server." This means that the recipient's server rejected receiving the message and considered it to be spam. This error can also be displayed if the recipient's email address is blocked.
- Soft bounces. This group has temporary delivery issues. The following reasons are why email addresses may bounce in this case.
- "Temporarily unavailable." This means that the last email failed to send for a reason beyond the service's control; for example, the user’s server was unavailable or it rejected the message.
- "Mailbox full." This means that the subscriber’s mailbox is full and can't receive any new email messages.
- "The email is too large." This means the contents of the email were too big to send.
These details can be found in your statistics report. Read about the reasons why email addresses may bounce in this article.