Summary
In September 2020, many email service providers (ESPs) and senders experienced a sudden halt in receiving Feedback Loop (FBL) complaint reports from Microsoft. This unexpected interruption, lasting several days, raised concerns within the email deliverability community about monitoring and maintaining sender reputation. The issue was widely discussed among industry professionals, highlighting the critical role FBLs play in managing email programs.
Key findings
- Interruption period: Microsoft FBL reports stopped for many senders around mid-September 2020 (specifically around the 17th or 18th).
- Widespread impact: Multiple ESPs and individual senders confirmed experiencing the same problem simultaneously, indicating a systemic issue.
- Data resumption: Reports eventually resumed, and crucially, they included backdated data, filling the gap from the interruption period. This helped senders catch up on complaint metrics.
- Monitoring challenges: The outage underscored the reliance on FBL data for real-time complaint monitoring and its direct link to inbox placement.
Key considerations
- Diversify monitoring: While FBLs are vital, having additional methods to monitor sender reputation and complaint rates is crucial for business continuity. This includes checking your Microsoft SNDS data.
- Understand FBL history: Familiarize yourself with the history of Microsoft's FBL program and its evolution.
- Impact on metrics: Periods of missing FBL data can artificially lower reported spam rates in the short term, potentially masking underlying issues.
- Contingency planning: Develop contingency plans for situations where critical data feeds are temporarily unavailable.
What email marketers say
The sudden disappearance of Microsoft FBL reports in September 2020 caused significant confusion and concern among email marketers. Many relied heavily on these reports for insights into recipient engagement and complaint rates. The absence of this data created a blind spot, making it challenging to quickly identify and address potential deliverability issues or manage sender reputation effectively. Marketers often shared their experiences in forums and communities, seeking confirmation and updates on the situation.
Key opinions
- Confirming the outage: Many marketers quickly confirmed that they were also not receiving FBL data, suggesting a widespread problem, not an isolated incident.
- Varying start dates: While most reported the halt around September 17th or 18th, some noted the absence of reports starting earlier, perhaps as early as September 13th.
- Impact on metrics: The lack of data meant marketers couldn't accurately gauge their complaint rates or respond to potential increases in spam complaints.
- Relief when restored: There was a collective sense of relief when reports resumed and were backdated, allowing marketers to reconcile their metrics.
Key considerations
- Proactive monitoring: Even with FBLs, marketers should continuously monitor other deliverability signals to identify problems early. Regularly check for increasing complaint rates.
- Community engagement: Engaging with the broader email community (e.g., through forums or social media) can help confirm widespread issues and share solutions.
- SNDS checks: During FBL outages, regularly checking Microsoft SNDS for any authorization email delays or data issues is recommended.
- Expect fluctuations: Even typically stable FBL feeds can experience temporary disruptions or data inconsistencies due to ISP system changes or maintenance.
Marketer view
Marketer from Email Geeks reports that their team had not received any FBL complaints from Microsoft since Thursday evening UTC time in mid-September. They had started a thread on Mailop to verify if others were impacted, expecting a positive confirmation.
Marketer view
Marketer from Email Geeks confirms the issue, stating that the last report they received was on midnight of the 18th of September. This aligns with other reports of a sudden halt in FBL data delivery.
What the experts say
Deliverability experts viewed the Microsoft FBL outage as a significant event that underscored the fragility of email ecosystem components. They emphasized that while FBLs are indispensable, sole reliance on any single data source can be risky. The incident provided an opportunity to reinforce best practices in data redundancy, monitoring, and communication within the industry. Experts also pointed out that such outages, while disruptive, are often temporary and resolved by ISPs through internal processes, including data backfilling.
Key opinions
- Systemic nature: Experts quickly identified the FBL interruption as a broad issue originating from Microsoft's side, rather than individual sender problems.
- Backend processing: It was theorized that Microsoft was likely experiencing internal processing delays or system maintenance that affected FBL generation and delivery.
- Data backfilling: The return of backdated FBL data was seen as a standard and positive resolution by the ISP, ensuring data integrity post-outage.
- Reputation impact: The incident highlighted how critical FBL data is for proactive sender reputation management and avoiding IP or domain blocklisting (or blacklisting).
Key considerations
- Holistic monitoring: Beyond FBLs, experts advise senders to leverage other tools like Microsoft SNDS and DMARC reports for a comprehensive view of deliverability.
- Communication with ISPs: Establishing direct lines of communication with ISPs for critical updates can minimize panic during service disruptions.
- Adaptation to changes: ISPs regularly update their filtering and reporting systems, which can sometimes lead to temporary data inconsistencies or outages. This can cause issues such as changes in Microsoft's email filters.
- Industry alerts: Monitor industry forums for timely alerts about widespread deliverability issues.
Expert view
Expert from Email Geeks explains that FBL outages, even temporary ones, can significantly impact an ESP's ability to monitor real-time abuse metrics, potentially leading to missed signals of declining sender reputation.
Expert view
Expert from Email Geeks emphasizes the importance of having backup monitoring systems in place, as relying solely on FBLs can leave senders vulnerable during unexpected service disruptions from ISPs.
What the documentation says
Official documentation from Microsoft and other ISPs typically outlines the purpose and mechanics of Feedback Loops, emphasizing their role in providing senders with insights into user complaints. While specific outages like the one in September 2020 are rarely documented beforehand, the general principles of FBL operation often imply that data availability can be subject to network conditions, processing queues, and system maintenance. Documentation usually highlights that FBLs are a privilege, not a guarantee, and require senders to adhere to best practices to maintain access.
Key findings
- Purpose of FBLs: Documentation defines FBLs as a critical mechanism for senders to receive notifications when recipients mark their emails as spam.
- Registration process: Access to FBL data typically requires senders to register their IP addresses or domains with the respective ISP's Postmaster tools.
- Data delivery variability: While consistent, documentation often implies that data delivery can experience delays or temporary interruptions due to system load or maintenance.
- Threshold requirements: Some FBLs only provide reports once a certain volume or complaint threshold is met, which could influence data visibility during low sending periods.
Key considerations
- Adherence to guidelines: Snders must strictly adhere to the ISP's guidelines for FBL usage to ensure continued access and accurate reporting.
- Understanding data flow: Familiarity with how FBL reports work, including forwarding and IP addresses, is beneficial.
- Complementary protocols: While powerful, FBLs should be used in conjunction with other authentication protocols like DMARC to build a robust sender reputation.
- Regular review: Regularly review official ISP Postmaster documentation for updates on FBL services and any known issues.
Technical article
Technical documentation from Microsoft explains that the Feedback Loop program (JMRP) is designed to help legitimate email senders maintain good sending reputations by providing insights into user complaints.
Technical article
An academic paper on FBLs clarifies that the timely delivery of complaint data is crucial for senders to identify and remove unengaged or complaining users from their mailing lists promptly.
Related resources
1 resources
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