Understanding Email Delivery Failures: Transient & Permanent Bounces
In BoldDesk, email delivery failures are categorized into two types:
- Transient Bounce
- Permanent Bounce
Understanding the difference between these helps in diagnosing and resolving email delivery issues effectively.
Transient Bounce
A transient bounce occurs when an email cannot be delivered due to temporary issues, such as a full inbox, server downtime, or network congestion. These failures are often resolved automatically, and the system may retry sending the email after a short period.
Most email systems automatically retry sending for a period of 48–72 hours. If delivery still fails, the system stops trying and the email is marked as permanent bounce.
Common Causes of Transient Bounce
- Recipient’s mailbox is full
- Recipient’s mail server is temporarily down
- Network timeout or delivery delay
- Greylisting by the recipient’s server
- DNS resolution issues
- Rate limiting by the recipient server
- Temporary SPF/DKIM/DMARC validation issues
- Email size exceeds recipient limits
- Temporary rejection by spam filters
Monitoring Transient Bounced Emails in BoldDesk
You can track transient bounce events directly from the Ticket Details page:
- Open the ticket and locate the specific message.
- Click on the More Actions menu.
- Select Email Delivery Status to view detailed delivery information.
Permanent Bounce
A permanent bounce indicates a lasting issue that prevents delivery, such as an invalid email address, a domain that no longer exists, or a recipient server that has blocked the sender. These failures require manual intervention, such as verifying the recipient’s email address or updating contact information.
Common Causes of Permanent Bounce
- Invalid or misspelled client email address
- Non-existent domain
- Deactivated or deleted email account
- Client’s server has blocked BoldDesk’s sending domain
- Strict anti-spam policies on the client’s server
- BoldDesk’s domain or IP is blacklisted
- No MX records for the client’s domain
- Policy restrictions preventing delivery
Monitoring Bounced Emails via Audit Logs
You can monitor both permanent and transient bounced emails through the audit logs. These logs offer detailed information about the errors. To access the logs, please follow the steps provided.
- Navigate to the Admin Center.
- Under the General section, click Audit Logs.
- Select Email Failure Logs to view detailed bounce information.
Transient bounce
Permanent bounce
