A sudden drop to zero in FBL spam rates and identifier counts, coupled with decreased inbox placement, indicates a significant email deliverability issue stemming from various potential causes. One common factor is a decline in sender reputation, resulting from poor sending practices, list hygiene issues (including spam traps and unengaged users), problematic content, or even changes in audience behavior or email provider algorithms. This can cause emails to be marked as spam, blocked entirely, or directed to the bulk/spam folder, preventing user interaction and spam reporting. Other technical issues can also contribute, such as misconfigured feedback loops (FBLs), authentication problems (SPF, DKIM, DMARC), or blocklisting. In specific cases, emails may be entering Gmail purgatory or being globally filtered due to new spam filters, thereby requiring direct bug reports to the client software company. Diagnosing the root cause necessitates a comprehensive assessment of sender reputation, technical configurations, list health, content quality, engagement levels, and policy adherence. Monitoring tools like Google Postmaster Tools, checking DNS records, observing open rates, and analyzing campaign changes become essential for identifying and resolving the underlying problem.
13 marketer opinions
A sudden drop to zero in FBL spam rates and identifiers, impacting inbox placement, suggests a significant shift in email delivery. Several factors could contribute, including changes in audience engagement, algorithm updates by email providers (like Gmail purgatory), or a decline in sender reputation. Issues with feedback loops (FBLs), list hygiene, authentication (SPF, DKIM, DMARC), content quality, sending volume, and the presence of spam traps in affiliate data can all play a role. It might also indicate emails are being blocked entirely or going directly to spam without being registered as complaints. Monitoring sender reputation tools (Google Postmaster Tools), checking DNS records, observing open rate drops, analyzing campaign changes, and ensuring correct configuration of mail servers and feedback loops are crucial steps in diagnosing and addressing the problem.
Marketer view
Email marketer from Mailchimp explains that sudden changes in delivery rates (and potentially related spam metrics) can stem from alterations in sending volume, content triggers, or recipient engagement. They advise reviewing recent campaign changes and segmenting lists based on engagement to improve deliverability.
25 Aug 2024 - Mailchimp
Marketer view
Marketer from Email Geeks recommends establishing a baseline for expected metrics from each affiliate and setting up alerts for deviations, in addition to email validation. They also advise throttling sends to affiliate leads to identify problems before they affect overall deliverability.
20 Feb 2022 - Email Geeks
3 expert opinions
A zero FBL spam rate and identifier count, coupled with decreased inbox placement, points to significant deliverability issues. One possibility is that emails are landing in the bulk/spam folder, preventing users from reporting them as spam, so no complaints are being registered. Also, there might be issues with the feedback loops (FBLs) themselves, leading to incorrect or missing spam reports. Finally, a complete drop in spam complaints alongside reduced inboxing often indicates aggressive blocking or filtering by ISPs, suggesting underlying problems with list quality, sending reputation, or content.
Expert view
Expert from Word to the Wise shares that a sudden and complete drop in spam complaints, along with decreased inbox placement, strongly suggests you're being blocked or filtered aggressively. Focus on identifying the cause of the filtering (list quality, sending reputation, content, etc.) and addressing it with the ISPs.
15 Jan 2025 - Word to the Wise
Expert view
Expert from Email Geeks shares that there is no spam to report if the email is in the bulk folder.
18 Dec 2024 - Email Geeks
4 technical articles
A zero FBL spam rate coupled with inbox placement issues may stem from several technical and policy-related causes, according to documentation from major email providers. A low or suddenly declining sender reputation, often resulting from poor sending practices, inadequate list hygiene, or problematic content, can lead to emails being marked as spam or blocked entirely. This can also be caused by a misconfigured Feedback Loop Reporting setup. Additionally, a complete absence of spam complaints or unusual metrics may indicate a total block, necessitating a review of blocklists and adherence to sending policies specified by platforms like Microsoft. In Gmail it could be a problem in the feedback loop. Diagnosing and rectifying these issues require careful attention to sender reputation, technical configurations, and policy compliance.
Technical article
Documentation from RFC explains that a misconfigured Feedback Loop Reporting setup may be causing an error. Verify with your email provider if you are getting the correct feedback loops.
26 May 2024 - RFC Documentation
Technical article
Documentation from Amazon SES Documentation explains that if your FBL spam rate and identifier counts in GTP suddenly went to zero, it could indicate that you've been completely blocked from sending to Gmail users, or there's a problem in the feedback loop. Double check settings are correct.
16 Oct 2024 - Amazon SES Documentation
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