Summary
Google may intentionally suppress detailed bounce codes for security and privacy reasons, particularly to thwart spammers. Instead, focus on maintaining a strong sender reputation by implementing proper email authentication (SPF, DKIM, DMARC), avoiding spam triggers, segmenting lists for relevant content, monitoring deliverability via Google Postmaster Tools, and promptly addressing any issues flagged within your Google Workspace account or identified through external reputation monitoring services. Troubleshoot potential header alterations and follow best practices to improve engagement metrics, thus positively influencing deliverability.
Key findings
- Security by Obscurity: Google might intentionally withhold detailed bounce codes as a security measure against spammers and phishers.
- Google Workspace Impact: Suspicious activity in a Google Workspace account can lead to entire account flagging.
- Authentication is Key: Proper implementation of SPF, DKIM, and DMARC is critical for email authentication.
- Reputation Monitoring: Actively monitoring domain and IP reputation is vital for identifying and addressing deliverability issues.
- Engagement Matters: Improving email engagement metrics (open and click-through rates) can positively influence deliverability.
- Forwarding Problems: Email forwarding can sometimes lead to header alterations and subsequent rejection.
Key considerations
- Use Google Postmaster Tools: Utilize Google Postmaster Tools to track domain reputation, spam rate, and other deliverability metrics.
- Implement Authentication: Configure SPF, DKIM, and DMARC records to authenticate your emails properly.
- Avoid Spam Triggers: Refrain from using spam trigger words and ensure your email content is relevant and valuable.
- Segment Your Lists: Segment email lists to send more targeted and relevant content, improving engagement.
- Maintain Clean Lists: Regularly clean your email lists to remove inactive or invalid addresses, reducing bounce rates.
- Monitor Blacklists: Use online tools to check if your domain or IP address is blacklisted.
- Contact Workspace Support: If you suspect your Google Workspace account is flagged, contact Google support for assistance.
- Address DMARC Failures: Investigate and resolve any DMARC authentication failures promptly.
- Consider Direct Subscriptions: In cases of forwarding issues, consider subscribing directly to services instead of relying on forwarding.
What email marketers say
12 marketer opinions
Google may reject emails without providing specific bounce codes for various reasons, including suspected spam or phishing activity, DMARC failures, or internal security measures. To address this, it's crucial to maintain a good sender reputation by adhering to email best practices, such as using proper authentication (SPF, DKIM, DMARC), avoiding spam trigger words, and segmenting email lists. Monitoring domain reputation through tools like Google Postmaster Tools and addressing issues promptly can also help improve email deliverability.
Key opinions
- Security Measures: Google may withhold bounce codes for security reasons, especially related to spam and phishing.
- Workspace Flagging: Suspicious activity within a Google Workspace account can lead to the entire account being flagged.
- Sender Reputation: Maintaining a good sender reputation is critical for email deliverability.
- Authentication: Proper email authentication (SPF, DKIM, DMARC) is essential to verify sender legitimacy.
- List Hygiene: Keeping email lists clean and sending relevant content reduces the risk of being flagged as spam.
- Engagement Metrics: Improving email engagement metrics (open and click-through rates) can positively impact deliverability.
Key considerations
- Monitor Reputation: Regularly monitor your domain reputation using Google Postmaster Tools and other relevant services.
- Authenticate Emails: Ensure emails are properly authenticated with SPF, DKIM, and DMARC records.
- Avoid Spam Triggers: Avoid using spam trigger words in your email content and subject lines.
- Segment Lists: Segment email lists to send more targeted and relevant content to recipients.
- Provide Unsubscribe Option: Make it easy for recipients to unsubscribe from your emails.
- Address DMARC Failures: Check DMARC reports and address any authentication failures promptly.
Marketer view
Email marketer from SparkPost advises monitoring sender reputation, keeping email lists clean, and sending relevant content to avoid being flagged as spam.
8 Jun 2023 - SparkPost
Marketer view
Email marketer from Litmus recommends focusing on improving email engagement metrics, like open and click-through rates, which can positively impact deliverability.
2 Oct 2021 - Litmus
What the experts say
3 expert opinions
Google's practice of not providing bounce codes when rejecting emails stems from security and privacy considerations, particularly in cases of suspected spam or phishing. Additionally, header alteration issues may cause rejections in specific forwarding scenarios. Overcoming these challenges involves proactively monitoring domain and IP reputation through tools like Google Postmaster Tools and focusing on establishing a trustworthy sending reputation.
Key opinions
- Security/Privacy: Lack of explicit bounce codes can be a deliberate security measure by Google.
- Header Alteration: Google might alter email headers during forwarding, leading to rejection.
- Sender Reputation: Building and maintaining a good sender reputation is paramount.
- Monitoring is key: Actively monitoring domain and IP reputation is critical.
Key considerations
- Bypass Forwarding: Consider bypassing forwarding from certain services and resubscribing directly.
- Use Postmaster Tools: Utilize Google Postmaster Tools to gain insights into domain reputation.
- Address Suspicious Content: Ensure emails are free of content that might trigger spam filters.
- Check Headers: Examine email headers for any alterations by intermediary servers.
Expert view
Expert from Word to the Wise emphasizes that actively monitoring your domain and IP reputation through tools like Google Postmaster Tools is vital for identifying and resolving deliverability issues, even if specific bounce codes are lacking.
23 Jul 2023 - Word to the Wise
Expert view
Expert from Email Geeks shares experience with Gmail rejecting forwarded emails from Dreamhost due to Google altering the headers in a way that it then doesn't like, and mentions the workaround was to resubscribe directly to Gmail.
17 May 2024 - Email Geeks
What the documentation says
5 technical articles
Email bounces occur for various reasons, including SPF, DKIM, and DMARC failures, recipient servers marking emails as spam, and non-compliance with DMARC policies. While SMTP enhanced status codes and NDRs (as used in Exchange Online) offer detailed information, understanding SPF records and DMARC policies is crucial for resolving deliverability issues and ensuring email authentication.
Key findings
- Authentication Failures: SPF, DKIM, and DMARC failures are common reasons for email bounces.
- Spam Filtering: Recipient servers may mark emails as spam, leading to rejection.
- DMARC Policies: DMARC policies determine how recipient servers handle emails that fail authentication.
- Enhanced Status Codes: SMTP enhanced status codes offer more granular information about delivery failures.
- NDRs in Exchange: NDRs in Exchange Online provide information about undelivered emails and troubleshooting steps.
Key considerations
- Implement Authentication: Ensure proper implementation of SPF, DKIM, and DMARC to authenticate emails.
- Review DMARC Policy: Understand and configure DMARC policies to control email handling.
- Troubleshoot Bounce Reasons: Investigate specific reasons for email bounces based on available error messages or NDRs.
- Consult RFCs: Refer to RFCs for detailed specifications on SMTP enhanced status codes and SPF records.
- Follow Google Guidance: Follow Google Workspace Admin Help for recommended troubleshooting steps.
Technical article
Documentation from DMARC.org explains the different DMARC policies (none, quarantine, reject) and how they instruct recipient mail servers to handle emails that fail DMARC authentication.
10 Feb 2025 - DMARC.org
Technical article
Documentation from Microsoft explains that Non-Delivery Reports (NDRs) in Exchange Online provide information about why an email was not delivered and how to fix the issue, also explaining the different types of error codes in use.
9 Sep 2022 - Microsoft Learn
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