What is the primary purpose of Microsoft SNDS?

The primary purpose of Microsoft SNDS is to provide senders with data insights into their IP addresses' email activity and reputation on Microsoft platforms, such as Outlook and Hotmail. It helps identify issues like spam complaints and spam trap hits.

Why might SNDS data not be updating or accessible?

SNDS data might not be updating or accessible due to various reasons, including system outages, technical glitches on Microsoft's side, or issues with your IP registration and verification within the SNDS portal. Occasionally, it might also be related to specific account or user permissions.

Can my emails still go to spam even if SNDS shows my IPs as "green"?

Yes, even if SNDS shows your IPs as "green" (indicating good reputation), your emails can still go to spam. This often happens if there are underlying issues related to email content, recipient engagement, or other behavioral factors that Microsoft's filters consider, which might not be fully reflected in the basic SNDS metrics.

What steps should I take if I suspect SNDS issues are affecting my deliverability?

If you suspect SNDS issues are affecting your deliverability, first verify your IP registrations and ensure all verification emails are received. Then, cross-reference SNDS data with your internal email analytics and other postmaster tools. If problems persist, consider reaching out to Microsoft's SNDS/JMRP support team for direct assistance.

How often should I check SNDS for updates on my IP reputation?

You should check SNDS for updates on your IP reputation regularly, ideally daily or at least several times a week, especially if you are a high-volume sender or are experiencing known deliverability challenges. Timely monitoring allows for quicker diagnosis and resolution of potential issues.

Knowledge base

/

Email deliverability

/

Troubleshooting

What are the recent issues and fixes related to SNDS?

Michael Ko

Co-founder & CEO, Suped

Published 13 May 2025

Updated 17 Aug 2025

6 min read

Microsoft's Smart Network Data Services (SNDS) is critical for understanding email performance within the Outlook and Hotmail ecosystem. It offers valuable insights into your IP reputation, spam complaint rates, and spam trap hits. Without this data, navigating Microsoft's spam filters can feel like flying blind.

While an indispensable resource, SNDS has had its share of operational issues and data inconsistencies. Staying informed about these challenges and their solutions is crucial for maintaining strong email deliverability.

Understanding SNDS and its data

Microsoft Smart Network Data Services (SNDS) provides senders with detailed feedback on their IP addresses' email activity on Microsoft platforms. This includes information on complaint rates, spam trap hits, and SmartScreen filter dispositions, which are all vital for maintaining a healthy sender reputation. You can find more details on its purpose and functionality on the Microsoft sender support site.

The tool uses a simple traffic light system, with green indicating good reputation, yellow suggesting potential issues, and red signifying serious problems. This system is designed to help senders identify and address deliverability issues proactively, ensuring their emails reach the inbox.

However, a common challenge is when SNDS data appears incomplete, delayed, or even entirely absent. This can severely hinder troubleshooting efforts, making it difficult to understand why emails might be landing in the junk folder despite seemingly good metrics. Some users report that SNDS data is limited and does not always provide sufficient insights to resolve issues.

Recent operational hiccups and data discrepancies

One of the most frustrating recent issues has been the lack of fresh data updates in SNDS, with many users reporting that data hasn't refreshed for several days. This means senders are operating with outdated or missing information, making it impossible to respond to real-time deliverability shifts. There have also been reports of issues with verification emails not sending, preventing new IP addresses or ranges from being registered.

When SNDS data is not displaying or accessible, it creates a significant blind spot for email marketers. It becomes challenging to diagnose issues like sudden drops in inbox placement or increased complaint rates. This can leave senders guessing about the root cause of their problems, often leading to prolonged deliverability headaches.

These data inconsistencies can also lead to discrepancies between SNDS reports and other internal email delivery data. For instance, you might see high delivery rates in your own platform, but SNDS indicates problems, or vice versa. Resolving these divergences requires careful cross-referencing and often, direct engagement with Microsoft's support channels. You can learn more about this in our article covering discrepancies between SNDS and SFMC reports.

When faced with SNDS issues, the first step is to confirm your IP addresses are correctly registered and verified within the system. Sometimes, the problem is as simple as a pending re-authorization request or a misconfigured entry. Ensuring your IP access is correctly set up is fundamental to receiving accurate data. More details on IP requirements for Microsoft SNDS can be found in our comprehensive guide.

A common, perplexing scenario occurs when SNDS reports all your IPs as "green" but you're still experiencing significant delivery problems, such as transactional emails going to spam. This often indicates that the issue lies beyond simple IP reputation, possibly involving content, recipient engagement, or other behavioral factors not fully reflected in basic SNDS metrics. Learn more about this by reading why transactional deliverability issues occur.

Beyond data accuracy and 'green' statuses, persistent issues like blocklistings (or blacklists) can arise if your sending practices trigger Microsoft's internal filters. Even if SNDS shows a clean bill of health, sudden spikes in complaints or spam trap hits (which SNDS does report) can lead to temporary or even long-term blocks.

Spam traps are another frequent cause of deliverability issues that SNDS can report on. Even with green metrics, hitting spam traps can severely damage your reputation. Regularly cleaning your email lists and maintaining good sending hygiene are crucial to avoid these pitfalls, as explained in our guide on what spam traps are and how they work.

Example SPF record for Microsoft integrationdns

v=spf1 include:_spf.example.com include:spf.protection.outlook.com -all

Common SNDS errors

Setup difficulties: Many users report difficulties with the initial setup, including verification emails not being received.
Data reliability: Data delays or complete outages can prevent timely monitoring of sender reputation.
Metrics confusion: Discrepancies between SNDS reported data and actual inbox placement are a frequent source of frustration.

Data issues

Delayed updates: SNDS sometimes shows no updates or significantly delayed information for your registered IP addresses.
Verification failures: Verification or re-authorization emails may fail to deliver, preventing access or crucial updates.

Deliverability impact

Blind diagnosis: Lack of accurate, timely data makes it nearly impossible to diagnose and respond to deliverability dips.
False positives: IPs showing green in SNDS can still face blocks or junking, indicating other underlying issues are at play.

Beyond SNDS: Broader deliverability considerations

While SNDS is invaluable for Microsoft, it's essential to remember that it's one piece of a larger email deliverability puzzle. A holistic approach includes robust email authentication protocols such as SPF, DKIM, and DMARC. These foundational elements verify your sending identity and significantly influence how mailbox providers perceive your emails. For a simpler explanation, see our article on DMARC, SPF, and DKIM.

Beyond technical configurations, sender reputation is heavily influenced by recipient engagement and content quality. High complaint rates, low open rates, or frequent bounces, even if not immediately reflected in SNDS, can signal problems to Microsoft's filters. Consistently sending valuable, wanted emails to engaged subscribers is key to long-term inbox success.

Views from the trenches

Best practices

Maintain clean email lists to minimize bounces and spam trap hits, enhancing your overall sender reputation.

Regularly monitor all relevant email authentication records like SPF, DKIM, and DMARC to ensure proper configuration.

Segment your audience and personalize content to improve engagement and reduce complaint rates.

Common pitfalls

Ignoring SNDS data delays, which can lead to delayed responses to deliverability issues and prolonged problems.

Relying solely on SNDS 'green' status without checking other deliverability metrics or user feedback.

Failing to clean inactive or unengaged subscribers from your lists, increasing the risk of spam traps.

Expert tips

Always keep a direct line of communication open with Microsoft's SNDS/JMRP support team for critical issues.

Cross-reference SNDS data with your internal analytics and other postmaster tools for a complete deliverability picture.

Implement a structured IP warm-up strategy for new IPs, even if SNDS shows initial positive feedback.

Expert view

Expert from Email Geeks says they were troubleshooting with the SNDS/JMRP Support Team and observed that SNDS requests for new data and re-authorization emails became functional again.

2023-10-15 - Email Geeks

Marketer view

Marketer from Email Geeks says they noticed that SNDS had not been showing updates for their accounts since October 11th.

2023-10-15 - Email Geeks

Final thoughts on SNDS troubleshooting

Navigating the complexities of Microsoft SNDS can be challenging, especially when facing data delays or inconsistencies. While recent issues have highlighted its vulnerabilities, SNDS remains a vital tool for senders aiming to achieve optimal inbox placement on Microsoft properties.

The key to successful email deliverability with Microsoft is not only to monitor SNDS diligently but also to proactively implement comprehensive authentication, maintain strict list hygiene, and quickly respond to any anomalies, even those not immediately apparent in SNDS data.