How to Use Microsoft SNDS to Monitor Your Sending Reputation
While Google Postmaster Tools gets most of the attention, Microsoft's Smart Network Data Services (SNDS) is equally important for monitoring your reputation with Outlook and Microsoft 365 recipients.
While Google Postmaster Tools gets most of the attention, Microsoft's Smart Network Data Services (SNDS) is equally important for monitoring your reputation with Outlook and Microsoft 365 recipients.
What SNDS is
SNDS is Microsoft's free tool for email senders to view data about their sending activity and reputation with Microsoft's email network. It provides data on spam complaints, trap hits, and sample message data for emails sent from your IP addresses.
What SNDS shows you
IP reputation data: The spam rate and complaint rate associated with your sending IPs. With Google Workspace or Microsoft 365, you are on shared IPs, so this data reflects the entire pool rather than your individual sending. Spam trap hits: Whether your emails have hit any of Microsoft's spam traps. Sample messages: Examples of emails you have sent that triggered filters, helping you identify content issues.
The Junk Mail Reporting Program (JMRP)
In addition to SNDS, Microsoft offers JMRP, which sends you complaint notifications when Outlook users mark your emails as junk. This is Microsoft's version of a feedback loop and gives you real-time data on which recipients are complaining.
Setting up SNDS
Visit the SNDS portal and register your sending IPs. If you are using Google Workspace or Microsoft 365 shared IPs, you may have limited access. In this case, focus on monitoring your deliverability through inbox placement testing and engagement metrics from your campaigns.
Using SNDS alongside Google Postmaster Tools
Together, these two tools give you visibility into how the two largest email providers view your sending. Discrepancies between them can be informative — for example, if your Gmail reputation is High but your Microsoft deliverability is poor, you may have a Microsoft-specific content or authentication issue.
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