If your emails are not sending or you’re receiving bounce-back messages, it usually means there’s a delivery issue between your email server and the recipient’s server. These messages, while sometimes technical, contain valuable information that helps identify the cause of the problem.
In most cases, bounce-backs occur due to server limits, blacklisting, incorrect email settings, or content issues.
Note: When contacting LyteHosting Support for assistance, please include a sample of the bounced message with full email headers enabled. This helps our team investigate the issue quickly.
Common Reasons for Email Bounces
These are the common reasons for email bounce-back:
1. Policy or Blacklist Issues: The recipient’s server rejected the message because your domain, IP, or email address appears on a blacklist or is flagged as spam.
- Example Error: SMTP 554 (rejected for policy reasons)
- Solution: Check if your server’s IP or domain is listed on a reputation service like Spamhaus. Contact the recipient to request whitelisting if necessary.
2. Recipient Quota or Invalid Address: The recipient’s inbox is full, or the email address is invalid.
- Example Error: SMTP 550 (recipient rejected - ERR016)
- Solution: Verify the email address for typos or reach out to the recipient to resolve quota issues.
3. Sending Limits Exceeded: Your account has reached the maximum number of allowed emails within a time period.
- Example Error: SMTP 452 (sender rejected)
- Solution: Wait for the limit to reset or send emails in smaller batches later.
4. DNS or Domain Issues: The domain’s DNS, MX, or PTR records are missing or misconfigured.
- Example Error: SMTP 550 (suspect invalid mailer domain)
- Solution: Check your DKIM, SPF, and PTR settings and fix any invalid DNS records.
5. Content-Related Blocks: Emails containing blacklisted URLs, malicious attachments, or spam-like content can be rejected.
- Example Error: SMTP 552 (virus-infected message)
- Solution: Remove suspicious URLs, disallowed file types, or flagged keywords before resending.
6. Server Overload or Temporary Queue: The email queue is full due to high usage.
- Example Error: SMTP 421 (Server Temporarily Not Available)
- Solution: Wait and resend later once resources are available.
7. Recipient Server Settings: The recipient’s mail server is temporarily rejecting the email due to greylisting or filtering.
- Example Error: SMTP 452 (requested action aborted)
- Solution: Retry sending after a short delay.
For Shared Hosting:
- If you’re on a shared hosting plan, your account shares an IP with other users. If another account sends spam, the shared IP may become blacklisted, causing temporary email delivery issues.
- This usually resolves within 48 hours, or you can request a dedicated IP to avoid future blacklisting.
These are some of the measures to take in preventing email bounces:
- Use proper DKIM, SPF, and DMARC records.
- Avoid sending bulk emails without permission.
- Regularly monitor your domain/IP reputation.
- Keep your email content clean and avoid spam phrases or links.
- Use approved email marketing tools for newsletters or mass emails.
If you’re unsure why your email bounced or how to resolve the issue, please open a support ticket and include the bounce message with full headers. Our team will investigate and guide you through the fix.
