Understanding Bounces, Denylists and How to Keep Your Emails Flowing
At Annature, we’ve implemented a robust email delivery system that prioritises sender reputation. Emails sent from our platform are processed through our email provider (Mandrill), which enforces strict rules to preserve this reputation. As part of this, any email that fails to deliver, bounces, or is marked as spam is automatically added to a denylist based on the nature and frequency of the failure.
🟡 Soft Bounces
Soft bounces typically occur when a recipient’s mailbox is full or when the receiving mail server—previously known to be available—is temporarily down at the time of sending. These issues are usually temporary and don’t necessarily indicate a problem with the recipient’s email address. However, to preserve our sending reputation, we automatically apply denylist rules based on how often the soft bounce occurs. On the first soft bounce, the email address is blocked for 24 hours. If it happens again, the block is extended to 7 days. A third soft bounce results in a 30-day block, and after a fourth occurrence, the address is permanently denylisted.
🔴 Hard Bounces
Hard bounces are more severe and generally indicate a permanent issue. These usually occur when the email address or domain doesn’t exist, or when we receive a definitive rejection from the recipient’s server, such as “mailbox does not exist.” In these cases, our platform takes a cautious approach. On the first hard bounce, the address is blocked for 30 days. If a hard bounce happens a second time, the address is permanently added to the denylist. This helps ensure we’re not repeatedly sending to invalid addresses, which could damage overall deliverability.
🚫 Marked as Spam
If a recipient marks an email as spam, we treat this as a serious indicator that the message was unwanted. To protect all our users and maintain trust with mail providers, any email address that marks an email as spam is automatically denylisted for 365 days. This long-term block helps prevent future deliverability issues and safeguards our sender reputation.
🔍 What Happens When an Email Fails
When an email fails to deliver for any reason, the sender is automatically notified via email. In most cases, this notification will include a diagnostic message that helps explain why the delivery attempt was unsuccessful.
If the sender opens the envelope from the dashboard, they’ll see the recipient’s status marked as failed. From there, they can review the specific error message and take any necessary next steps to resolve the issue—such as confirming the recipient’s address or contacting support if a denylist is involved.
Additionally, Organisation Owners can view the status of all sent emails via a dedicated page in the platform. Under Settings > Email History, you’ll find a comprehensive log of each email, including timestamps for when it was sent, delivered, opened, and whether any key actions were taken—such as clicking a button or link.
🛠 What to Do If An Email Is Blocked
If an email has bounced or been blocked and you believe the address is valid, you can reach out to our support team. We’ll review the denylist status of the recipient and, if appropriate, remove the block. Once the block is lifted, you can easily resend the message from your end.
We can remove an address from our block list, but that might not always fix the delivery issue. If emails still bounce, the problem could be on the recipient’s side. Please ask them or their IT team to check their inbox settings.
Email deliverability issues can be frustrating, but with our transparent system and responsive support, we aim to make troubleshooting and resolution as smooth as possible.