A bounce message is also called a Non-Delivery Report/Receipt (NDR). It's an automated message from the recipient's email server with details about the specific problem with the email delivery. Complete details about the bounce type and server response are available in the Recipients tab of sent marketing emails. For one-to-one sales emails, bounce details are available in the email engagement on the contact timeline.
Please note:
Rejected by recipient's email security filter: the recipient's mailbox can't be reached. HubSpot drops contacts who bounce for this reason from future marketing emails. To solve the problem, ask the contact to whitelist your sending IP addresses, then unbounce the contact in HubSpot.
Temporary technical issue with the recipient's email: the recipient's server may be overloaded, timing out, or undergoing some configuration changes that prevented it from accepting the message. Create a clone of the original email and send it to the affected contacts at a later date. For a one-to-one sales email, try sending your message again at a later date.
Rejected by recipient's email security filter: there's a temporary problem with the recipient's server or HubSpot's sending IP addresses. To solve the problem, ask the contact to whitelist your sending IP addresses. Then create a clone of the original email and send it to the affected contacts at a later date. For a one-to-one sales email, try sending your message again at a later date.
Your IT team has not authorized HubSpot to send emails on your behalf: your IT team set up a custom DMARC policy that needs to be updated to include HubSpot. Reach out to your IT team to send them documentation about using a DMARC policy with HubSpot.
Temporary technical issue: there may have been a temporary technical problem with the recipient's email server or HubSpot's email server. Create a clone of the original email and send it to the affected contacts at a later date. For a one-to-one sales email, try sending your message again at a later date.