A hard email bounce, also known as a permanent bounce or a non-delivery report (NDR), occurs when an email cannot be delivered to the recipient, and the reason for the failure is considered permanent. In other words, the email is undeliverable, and further attempts to send it will likely result in the same outcome. There are several reasons for hard email bounces:
- Invalid Recipient Address: The email address you’re trying to send to doesn’t exist or is misspelled.
- Domain Doesn’t Exist: The domain of the recipient’s email address (e.g., the part after the “@” symbol) doesn’t exist or is misspelled.
- Recipient Mailbox Full: The recipient’s mailbox is at its storage capacity, and they need to clear space before receiving new emails.
- Blocked Sender: The email server has blocked the sender’s domain or IP address, often due to a history of sending spam or suspicious emails.
- Recipient’s Email Server Down: The recipient’s email server is temporarily or permanently unavailable.
To avoid hard email bounces, follow these best practices:
- Maintain a Clean Email List: Regularly clean and update your email list to remove invalid or inactive email addresses. Use email verification tools to identify and remove hard bounces.
- Implement Double Opt-In: Use a double opt-in process for subscribers, which requires them to confirm their email addresses by clicking a link in a confirmation email. This reduces the chances of invalid or mistyped email addresses being added to your list.
- Monitor Sender Reputation: Maintain a good sender reputation by following email marketing best practices and avoiding spammy behaviour. This can help prevent your domain or IP address from being blocked.
- Use Email Authentication: Implement SPF, DKIM, and DMARC authentication protocols to prove the authenticity of your emails, reducing the likelihood of your emails being rejected due to spoofing or phishing concerns.
- Monitor Email Delivery Reports: Regularly review email delivery reports and bounce messages to identify and address delivery issues promptly.
- Respect Unsubscribe Requests: Make it easy for recipients to unsubscribe from your emails, and promptly remove them from your list when they opt out.
- Limit Sending Volume: If you’re sending emails in large volumes, consider gradually increasing your sending volume to avoid overloading your email server or being mistaken for a spammer.
By following these practices, you can reduce the risk of hard email bounces and maintain a healthier email marketing strategy with improved deliverability.