Summary
Experiencing close-to-zero email open rates on a specific IP pool is a multifaceted issue with potential causes ranging from technical glitches to sender reputation problems. Possible culprits include broken open tracking, emails being blocked or filtered as spam due to low IP/domain reputation, exceeding sending limits, improper IP warm-up, list hygiene issues, and authentication failures. Thorough investigation, testing, and adherence to best practices are essential to diagnose and resolve the problem.
Key findings
- Tracking Issues: Broken open tracking can falsely report zero open rates; especially if the issue across all ISPs, test tracking mechanisms.
- Reputation Problems: Low IP and domain reputation can lead to emails being filtered as spam or blocked entirely.
- Deliverability Issues: Email may be queued and not sent by ESP or the system may be throttling volume.
- Technical Issues: Technical issues can include problems with your event collectors.
- Volume Limits: Exceeding sending limits set by mailbox providers can result in delays or blocks.
- IP Warm-up: Failing to properly warm up new IPs can damage sender reputation and impact deliverability.
- List Hygiene: Poor list hygiene, including invalid or unengaged addresses, negatively affects deliverability.
- Authentication Failures: Lack of proper authentication (SPF, DKIM, DMARC) can cause emails to be flagged as spam.
- DNS Configuration: Improper DNS configuration, missing or incorrect reverse DNS (PTR) records can negatively impact deliverability.
Key considerations
- Verify Tracking: Test and verify open tracking across different email clients and browsers.
- Monitor Reputation: Monitor IP and domain reputation using tools like Google Postmaster Tools.
- Check Deliverability: Use seed lists and inbox placement tests to check if emails are reaching the inbox.
- Review ESP Settings: Check with ESP if emails are stuck in queue and make sure there are no technical issues
- Warm-up IPs: Gradually warm up new IPs by slowly increasing sending volume.
- Clean Lists: Regularly clean email lists to remove invalid and unengaged subscribers.
- Implement Authentication: Ensure proper SPF, DKIM, and DMARC records are configured.
- Review DNS: Make sure that the DNS configuration is correct and that the reverse DNS is properly set up.
What email marketers say
12 marketer opinions
Experiencing near-zero email open rates on a specific IP pool can stem from various deliverability issues, technical problems, or sender reputation concerns. Key areas to investigate include IP warm-up, sender reputation, email authentication (SPF, DKIM, DMARC), list hygiene, open tracking functionality, throttling by the ESP, and potential issues with event collectors. It's also important to check for blacklisting, spam filter triggers, and sending volume anomalies.
Key opinions
- IP Reputation: Low IP reputation due to spam complaints, blacklisting, or sudden volume increases can lead to near-zero open rates.
- List Hygiene: Poor list hygiene, including invalid or unengaged addresses, negatively impacts deliverability.
- Authentication: Lack of proper authentication (SPF, DKIM, DMARC) can cause emails to be flagged as spam.
- Open Tracking Issues: Broken open tracking can falsely report zero open rates.
- ESP Throttling: The ESP might be throttling email sending rates, impacting open rates.
- IP Warm-up: Failing to properly warm up a new IP address can damage sender reputation.
- Event Collector Problems: Issues with the event collector can disrupt tracking and reporting.
Key considerations
- Monitor IP Reputation: Regularly monitor IP reputation using tools like Google Postmaster Tools and address any issues promptly.
- Implement Authentication: Ensure proper email authentication (SPF, DKIM, DMARC) is in place to verify email legitimacy.
- Clean Email Lists: Regularly clean email lists to remove invalid and unengaged subscribers.
- Test Open Tracking: Test open tracking functionality across different email clients and devices to ensure accuracy.
- Investigate ESP: Check with your ESP regarding any potential throttling or queueing issues.
- Warm-up New IPs: Gradually warm up new IP addresses by slowly increasing sending volume over time.
- Spam Testing: Ensure emails are not ending up in the spam folder, test using different email accounts and services.
Marketer view
Email marketer from EmailonAcid.com responds that near-zero open rates could be a result of broken open tracking. Images, which trigger tracking, might be blocked by default by email clients or firewalls. It is also possible there is a problem with the tracking pixel. Test email clients to diagnose tracking issues.
15 Nov 2024 - EmailonAcid.com
Marketer view
Email marketer from Stackoverflow says to always test emails with multiple email accounts (gmail, hotmail, yahoo, etc) to see if they're landing in spam. They also indicate you need to do this to determine inbox placement.
12 Jun 2025 - Stackoverflow
What the experts say
3 expert opinions
Experiencing very low or zero email open rates on a specific IP pool often indicates a deliverability or tracking issue. It is important to determine whether the problem stems from the emails not reaching the inbox, a failure in tracking opens, or a poor sender reputation due to transitioning to a new IP pool. Testing deliverability and verifying tracking are crucial first steps, followed by IP warm-up and authentication checks.
Key opinions
- Tracking Error: The near-zero open rate might be a result of a tracking error, especially if the issue affects all ISPs. Test by sending a test email and loading a pixel.
- Deliverability Issue: Emails may not be reaching the inbox. Check deliverability using seed lists to confirm placement.
- New IP Reputation: Transitioning to a new IP pool often leads to deliverability challenges due to the lack of a sending reputation.
Key considerations
- Verify Tracking: Test email open tracking to rule out issues with tracking mechanisms.
- Assess Deliverability: Use seed lists or similar methods to assess whether emails are landing in the inbox or spam folder.
- Warm-up IP: If using a new IP pool, gradually warm up the IPs by slowly increasing sending volume over time.
- Check Authentication: Review DNS settings and ensure proper email authentication (SPF, DKIM, DMARC) is configured.
Expert view
Expert from Spam Resource shares that if you're seeing very low or zero engagement rates, particularly after changing something (like an IP pool), it's crucial to investigate the underlying cause. Suggests checking deliverability using seed lists or similar methods to ensure emails are actually reaching the inbox.
19 Jul 2022 - Spam Resource
Expert view
Expert from Word to the Wise explains that when transitioning to a new IP pool, it's common to experience deliverability challenges initially. This is because the new IPs lack a sending reputation. Gradually warming up the IP addresses by slowly increasing the sending volume is crucial to build a positive reputation with mailbox providers. Also check DNS settings and make sure to review authentication.
23 Jun 2024 - Word to the Wise
What the documentation says
5 technical articles
Experiencing close-to-zero email opening rates on a specific IP pool can be attributed to sender reputation issues, exceeding sending limits imposed by mailbox providers, or lacking essential email authentication configurations. Maintaining a positive sender reputation with major providers like Gmail and adhering to their guidelines is crucial. Additionally, proper DNS configurations, including reverse DNS records, and implementing SPF and DMARC policies, are vital for ensuring email deliverability and preventing emails from being marked as spam or blocked.
Key findings
- Sender Reputation: Low sender reputation with providers like Gmail results in emails being marked as spam or blocked.
- Sending Limits: Exceeding Microsoft's sending limits or being throttled leads to delayed or blocked emails.
- Reverse DNS: Lack of a proper reverse DNS (PTR) record can negatively impact deliverability as it affects sender verification.
- SPF Records: Absence of SPF records, or sending from IPs not listed in the SPF record, increases the likelihood of emails being rejected.
- DMARC Policies: Failure to implement DMARC policies exposes the domain to spoofing and phishing attacks, impacting deliverability.
Key considerations
- Monitor Reputation: Regularly monitor sender reputation using Google Postmaster Tools and other relevant tools.
- Adhere to Limits: Ensure compliance with sending limits imposed by mailbox providers like Microsoft.
- Configure rDNS: Set up a proper reverse DNS (PTR) record for your sending IP.
- Implement SPF: Implement SPF records to define authorized sending IPs.
- Implement DMARC: Implement DMARC policies to protect the domain from unauthorized use and enhance deliverability.
Technical article
Documentation from DMARC.org explains that implementing DMARC (Domain-based Message Authentication, Reporting & Conformance) policies allows email senders to protect their domain from unauthorized use, such as spoofing and phishing attacks. DMARC helps ensure that only legitimate emails are delivered, improving overall email security and deliverability, which prevents emails getting caught as spam.
13 May 2023 - DMARC.org
Technical article
Documentation from Google explains that sender reputation is crucial for Gmail deliverability. A low reputation means emails are more likely to be marked as spam or blocked, resulting in zero opens. Monitoring your reputation in Google Postmaster Tools and adhering to Google's sender guidelines is essential.
12 Aug 2022 - Google
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