Summary
Despite a good domain reputation, emails may still go to spam after IP warming due to a multitude of factors. Incorrect or incomplete email authentication (SPF, DKIM, DMARC) for the new IP is a major issue. Other factors include technical configuration problems (rDNS, HELO), content triggering spam filters, unexpected reputation changes post-warming, and the actions of other users on shared IPs. Furthermore, low engagement metrics, sending to inactive addresses, inconsistent volume, and not monitoring feedback loops also contribute. Properly warming the IP with gradual increases, practicing list hygiene, ensuring relevant content, and monitoring sender reputation are critical for inbox placement.
Key findings
- Authentication: Incorrect or incomplete SPF, DKIM, and DMARC configurations for the new IP address are a primary cause of deliverability issues.
- Technical Configuration: Incorrect rDNS, HELO settings, IP source, and SWIP status can negatively impact deliverability.
- Content: Email content may contain spam triggers, leading to filtering.
- Reputation: IP reputation can change unexpectedly post-warming, necessitating constant monitoring.
- Shared IP: On shared IPs, the actions of other users affect deliverability regardless of your domain reputation.
- Engagement: Low open rates, click-through rates, and high spam complaint rates negatively impact inbox placement.
- List Quality: Sending to inactive or unengaged email addresses damages sender reputation.
- Volume: Fluctuations in email sending volume can cause deliverability problems.
Key considerations
- Authentication Check: Meticulously verify SPF, DKIM, and DMARC records for the new IP address.
- Technical Audit: Perform a thorough audit of rDNS, HELO settings, IP source, and SWIP status.
- Content Review: Regularly review email content for potential spam-triggering keywords.
- Reputation Monitoring: Continuously monitor IP reputation and adjust sending practices accordingly.
- Dedicated IP Consideration: If using a shared IP, consider moving to a dedicated IP if problems persist.
- Warming Process: Gradually warm up the IP address with small batches to engaged subscribers.
- List Hygiene: Regularly clean email lists to remove inactive subscribers and invalid addresses.
- Feedback Loops: Enroll in feedback loops with major ISPs to identify and address spam complaints.
- Consistent Volume: Maintain a consistent email sending volume.
- Segmentation: Segment your list and send relevant content
- Testing: Use seed list testing to monitor deliverability issues across different ISPs.
What email marketers say
11 marketer opinions
Emails may land in spam after IP warming despite a good domain reputation due to a combination of factors. These include incorrect or incomplete email authentication (SPF, DKIM, DMARC) setup for the new IP, sending to inactive or unengaged email addresses, inconsistent sending volumes, content triggering spam filters, and not adequately monitoring or reacting to deliverability metrics. Gradual IP warming, proper list hygiene, relevant content, engagement with feedback loops, consistent volume, and thorough testing are crucial for maintaining good inbox placement.
Key opinions
- Authentication: Incomplete or incorrect SPF, DKIM, and DMARC configurations post-IP warming can lead to deliverability issues.
- Spam Triggers: Spammy words and phrases, as well as HTML rendering issues, can trigger spam filters.
- Engagement Metrics: Low open rates, click-through rates, and high spam complaint rates negatively impact inbox placement.
- Warming Process: Incorrectly warming IPs with high volumes or sending to unengaged segments can cause delivery problems.
- List Quality: Sending to inactive email addresses, bounces, or spam traps damages sender reputation.
- Volume: Sending inconsistent volume can cause delivery issues, even with domain reputation.
Key considerations
- Authentication Check: Verify and correct SPF, DKIM, and DMARC records for the new IP address.
- Content Review: Review email content for spam triggers and ensure proper HTML rendering across different email clients.
- Engagement Monitoring: Monitor open rates, click-through rates, and spam complaints, and adjust sending practices accordingly.
- Gradual Warming: Warm up the IP address gradually, starting with small batches of engaged subscribers.
- List Hygiene: Clean email lists regularly to remove inactive subscribers, invalid email addresses, and spam traps.
- Feedback Loops: Enroll in feedback loops with major ISPs to identify and address spam complaints quickly.
- Consistent Volume: Ensure a consistent volume of emails daily.
- Segmentation: Segment your lists and send targeted content
- Testing: Use seed list testing to monitor deliverability issues
Marketer view
Email marketer from Stack Overflow recommends using email testing tools to preview emails across different email clients and devices, ensuring optimal rendering and reducing the likelihood of being marked as spam.
13 Oct 2022 - Stack Overflow
Marketer view
Email marketer from Campaign Monitor explains that segmenting your email list and sending targeted content to specific groups can improve engagement metrics and reduce the likelihood of emails being marked as spam.
27 Dec 2023 - Campaign Monitor
What the experts say
5 expert opinions
Emails may still land in spam post-IP warming, even with a strong domain reputation, due to several technical and environmental factors. These include incorrect rDNS or HELO settings, improperly configured or verified SPF, DKIM, and DMARC records (especially crucial for new IPs), content that triggers spam filters, unexpected reputation changes post-warming requiring vigilant monitoring, or issues related to shared IP environments where other users' behavior affects deliverability. Consistent volume and persistence are also important if all technical aspects are correctly configured.
Key opinions
- Technical Configuration: rDNS, HELO settings, IP source, and SWIP status are critical technical elements to verify during IP warming.
- Authentication: Meticulous verification of SPF, DKIM, and DMARC configurations is essential, especially for new IPs.
- Content Filtering: Email content may contain triggering keywords that activate spam filters.
- Reputation Changes: IP reputation can change unexpectedly post-warming, requiring ongoing monitoring.
- Shared IP Impact: In shared IP environments, the actions of other users can negatively affect deliverability.
- Volume and Persistence: Maintaining consistent sending volume and persistent effort are crucial if all other factors are correctly configured.
Key considerations
- Technical Audit: Conduct a thorough audit of rDNS, HELO settings, IP source, and SWIP status.
- Authentication Verification: Verify and meticulously configure SPF, DKIM, and DMARC records for the new IP.
- Content Review: Review email content for potential spam-triggering keywords.
- Reputation Monitoring: Continuously monitor IP reputation post-warming for any unexpected changes.
- Dedicated IP: Consider switching to a dedicated IP if deliverability issues persist in a shared IP environment.
- Consistent Volume: Maintain a consistent email sending volume to build and maintain a positive sender reputation.
Expert view
Expert from Spam Resource explains that even with a good domain reputation, issues during or after IP warming can stem from poor email authentication configurations (SPF, DKIM, DMARC). He emphasizes the need to meticulously verify these settings and ensure they are correctly implemented for the new IP address.
26 Mar 2024 - Spam Resource
Expert view
Expert from Email Geeks suggests checking rDNS, HELO settings, IP source and SWIP status, neighbors, upstream ASN, and spam destination when troubleshooting IP warming issues.
11 Jun 2024 - Email Geeks
What the documentation says
5 technical articles
Emails may land in spam after IP warming, despite a good domain reputation, because of technical and policy requirements outlined by major email providers and industry standards. These include proper email authentication using SPF, DKIM, and DMARC; maintaining low spam complaint rates (below 0.1% as per Google's guidelines); avoiding sending unsolicited or unwanted email; making unsubscribing easy; and monitoring sender reputation with ISPs like Microsoft Outlook. Effective sender reputation management is vital for consistent inbox placement, as email providers use various signals including content, user feedback, and engagement metrics to filter emails.
Key findings
- Authentication: Proper email authentication (SPF, DKIM, DMARC) is a fundamental requirement for deliverability.
- Spam Rate: Maintaining a low spam complaint rate (ideally below 0.1%) is crucial for inbox placement.
- Unsolicited Mail: Avoid sending unsolicited or unwanted email to prevent being marked as spam.
- Unsubscribe Process: Making it easy for recipients to unsubscribe is essential for compliance and maintaining a good sender reputation.
- Sender Reputation: Sender reputation is a critical factor influencing inbox placement, monitored by ISPs using various signals.
Key considerations
- Implement Authentication: Implement and verify SPF, DKIM, and DMARC records for all sending domains.
- Monitor Spam Complaints: Monitor and address spam complaints promptly to keep the rate below the recommended threshold.
- Obtain Consent: Ensure recipients have explicitly consented to receive emails.
- Simplify Unsubscribing: Provide a clear and easy unsubscribe process in every email.
- Reputation Monitoring: Regularly monitor sender reputation with major ISPs like Microsoft and Google.
Technical article
Documentation from Validity (formerly ReturnPath) notes that sender reputation is a critical factor in email deliverability. Maintaining a positive reputation with ISPs is essential for inbox placement.
2 Apr 2022 - Validity
Technical article
Documentation from Google Bulk Sender Guidelines specifies that senders must authenticate their email using SPF, DKIM, and DMARC. They also must keep spam rates below 0.1% and avoid sending unwanted mail. They must also make it easy to unsubscribe.
17 Oct 2024 - Google Bulk Sender Guidelines
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