Bounce Classifications

A bounce occurs when an email message is rejected by the recipient's mail server and returned to the sender. Velocity360 automatically processes these bounce messages to protect your sending reputation.

A hard bounce is a permanent delivery failure. This happens for reasons that are unlikely to change, such as:

• The email address does not exist.
• The domain name (e.g., @company.com) does not exist.
• The recipient's email server has blocked delivery.

When Velocity360 receives a hard bounce, it automatically adds that email address to a suppression list and will not attempt to send to it again. This is critical for protecting your sender reputation.

A soft bounce is a temporary delivery failure. This means the email address is valid, but the server rejected it for a temporary reason, such as:

• The recipient's mailbox is full.
• The email message is too large.
• The mail server is temporarily offline or overloaded.

Velocity360 will attempt to re-send the email a few times over a 24-hour period. If it continues to soft bounce, it will be marked as such, but the contact will not be permanently suppressed.