A bounced contact means that your mailings have not been delivered to the email address of the contact. When you send out a mailing the bounced (and unsubscribed) contacts are automatically removed from the mailing list.
Bounces are generally divided into two categories – soft or hard.
A soft bounce means that the mailing reaches the recipient’s mail server, but haven’t been delivered to the recipient’s inbox. This might be because:
Hard bounces means that your mailings cannot be delivered at all. This might be because:
When you restore a bounced contact, the contact is only restored for future mailings. Old mailings are not resent again.