Summary
Gmail may display warning messages despite emails passing DMARC due to a multitude of factors beyond basic authentication. These include DNS issues, sender reputation problems (such as low scores or user complaints), content triggering spam filters, misconfigured or inconsistent authentication records (DKIM, SPF), unusual sending patterns, IP blocklisting, low engagement rates (open and click rates), and discrepancies between authentication and sender reputation. Diagnosing the specific cause often requires using tools like aboutmy.email, Google Postmaster Tools, or deliverability testing platforms.
Key findings
- Authentication Is Not Enough: Passing DMARC alone does not guarantee inbox placement or prevent warnings. Gmail considers numerous other factors.
- Sender Reputation is Crucial: Sender reputation is a primary driver of warnings. Factors impacting reputation include user complaints, engagement levels, and IP/domain history.
- Content Matters: Email content can trigger spam filters and warnings even with valid authentication. Avoid spammy keywords, excessive images, and poor HTML coding.
- Authentication Consistency is Key: Inconsistent DKIM signatures, SPF alignment issues, and misconfigured records can lead to warnings.
- Sending Infrastructure Impacts Deliverability: Inconsistent sending IPs, lack of a consistent sending history, and IP blocklisting affect deliverability.
Key considerations
- Check DNS Settings: Ensure proper DNS configuration and resolve any DNS-related issues.
- Monitor Sender Reputation: Use tools like Sender Score and Google Postmaster Tools to monitor sender reputation.
- Review and Optimize Content: Refine email content to avoid triggering spam filters.
- Verify Authentication Records: Regularly check and ensure correct configuration of DKIM and SPF records across all sending sources.
- Maintain IP Consistency and Warm-Up: Use consistent and reputable IPs for sending, and gradually warm up new IPs or domains.
- Monitor Engagement: Track open and click rates to ensure emails are engaging and relevant to recipients.
- Use Deliverability Testing Tools: Employ deliverability testing tools to identify and resolve potential issues.
What email marketers say
9 marketer opinions
Gmail may display warning messages despite emails passing DMARC due to factors beyond authentication, including low sender reputation, content triggering spam filters, inconsistent DKIM signatures, poor alignment of SPF and DKIM records, inconsistent sending IPs, lack of a consistent sending history, and the overall email engagement.
Key opinions
- Sender Reputation: Low sender reputation is a major factor. Gmail considers sender reputation even if DMARC passes, so maintaining a good reputation by sending high-quality content and warming up IPs is crucial.
- Content Issues: Email content can trigger spam filters. Certain keywords, excessive images, or poor HTML coding can lead to warnings.
- Authentication Alignment: Inconsistent DKIM signatures or misalignment of SPF and DKIM records can cause warnings. Ensuring correct alignment and consistent authentication practices is essential.
- Sending Infrastructure: Inconsistent sending IPs or lack of consistent sending history can result in Gmail distrusting messages. Using consistent and reputable IPs and gradually warming up new sending sources is recommended.
Key considerations
- Monitor Sender Score: Regularly check and maintain a good sender score, as it reflects sending reputation.
- Content Review: Review email content to avoid spam triggers, ensuring clean and engaging content.
- Check Authentication: Verify DKIM and SPF alignment, ensuring they are correctly configured across all sending sources.
- IP Consistency: Ensure emails are sent from consistent and reputable IPs.
- Warm-up IPs: Gradually warm-up new sending sources to establish a good reputation.
- Use Testing Tools: Utilize deliverability testing tools to identify specific issues and ensure optimal email configurations.
Marketer view
Email marketer from GlockApps recommends using their deliverability testing tool to check for specific issues. The tool can identify if there are SPF, DKIM or DMARC issues or problems with the content.
30 Aug 2022 - GlockApps
Marketer view
Marketer from Email Geeks asks if the issue is with Tim Starr's domain and if they are using any inbound filter or SEG that rewrites DKIM or modifies message content.
20 Dec 2021 - Email Geeks
What the experts say
4 expert opinions
Gmail may display warning messages despite emails passing DMARC for various reasons. These include DNS failures, inconsistent DNS results, or mail forwarding issues. It's also due to DMARC only verifying sender identity, not email content or sender reputation. Poor sender reputation from user complaints, low engagement rates, and discrepancies between authentication and reputation are also potential causes. Tools like aboutmy.email can assist in diagnosing the specific issue.
Key opinions
- DNS Issues: DNS failures, inconsistent DNS results, or mail forwarding can cause Gmail warnings.
- DMARC Limitations: DMARC only verifies sender identity, not content or reputation.
- Reputation Impact: Poor sender reputation, user complaints, and low engagement trigger warnings.
- Reputation Discrepancy: Discrepancies between authentication and reputation lead to warnings.
Key considerations
- Check DNS: Investigate and resolve any DNS failures, inconsistencies, or mail forwarding issues.
- Monitor Reputation: Actively monitor and improve sender reputation by addressing user complaints and boosting engagement.
- Diagnose with Tools: Utilize tools like aboutmy.email to diagnose specific issues affecting deliverability.
Expert view
Expert from Spam Resource explains that Gmail may show a warning despite DMARC passing because DMARC only verifies the sender's identity, not the email's content or the sender's reputation. Low engagement rates or problematic content can trigger warnings.
18 Nov 2024 - Spam Resource
Expert view
Expert from Word to the Wise responds that Gmail warnings often occur due to a discrepancy between authentication and sender reputation. Even with correct authentication, poor sender reputation from user complaints or low engagement can trigger warnings.
17 Oct 2021 - Word to the Wise
What the documentation says
5 technical articles
Gmail's warning messages, even when DMARC passes, stem from factors beyond authentication, including unusual sending patterns, user-reported spam, misconfigured authentication records, sender reputation, engagement levels, and IP blocklisting. Gmail algorithms consider these factors to determine the need for warnings. Monitoring Google Postmaster Tools, feedback loops, and IP reputation tools like Microsoft's SNDS is crucial for identifying and addressing deliverability issues.
Key findings
- Beyond Authentication: Gmail’s warning system considers factors beyond DMARC authentication, such as sending patterns and user feedback.
- Reputation and Engagement: Sender reputation and user engagement (open and click rates) significantly impact deliverability, even if DMARC passes.
- IP Blocklisting: IP addresses on blocklists can cause warnings regardless of DMARC status.
Key considerations
- Monitor Sending Patterns: Analyze and correct any unusual sending patterns that could trigger spam filters.
- Review Authentication: Ensure authentication records are correctly configured and regularly reviewed.
- Boost Engagement: Improve email relevance and engagement to increase open and click rates.
- Check IP Reputation: Regularly check IP reputation using tools like Microsoft's SNDS and address any blocklisting issues.
- Use Postmaster Tools: Utilize Google Postmaster Tools for detailed insights into deliverability issues and sender reputation.
Technical article
Documentation from DMARC.org details that even if a message passes DMARC, Gmail's algorithms consider other factors, like sender reputation and user engagement, to determine if a warning is necessary. Reviewing feedback loops and postmaster tools can help identify issues.
17 Jan 2024 - DMARC.org
Technical article
Documentation from Microsoft shares that Gmail's reputation filtering can flag emails if the sending server's IP address is on a blocklist, even if DMARC passes. Regularly check IP reputation using tools such as Microsoft's SNDS.
18 Apr 2022 - Microsoft
