MEmail Deliverability Glossary

Microsoft SNDS (Smart Network Data Services)

Microsoft's free service showing sending data and filter verdicts for Outlook.com and Hotmail delivery — the Microsoft equivalent of Google Postmaster Tools.

Microsoft SNDS is a free service by Microsoft that provides senders with data about email delivery performance to Outlook.com, Hotmail, and Live.com recipients. It is the Outlook/Microsoft equivalent of Google Postmaster Tools.

What SNDS provides:

Data per sending IP address
Message volume and trap hit counts
Spam complaint rates
Filter verdict breakdown (Good / Neutral / Red = blocked)
JMRP (Junk Mail Reporting Program) complaint data

SNDS traffic light system:

Green (Good): < 0.3% complaint rate; normal delivery
Yellow (Neutral): 0.3–1% complaint rate; some filtering
Red: > 1% complaint rate; mail is being blocked

Registration: Request access at postmaster.live.com. You must verify ownership of each IP you want to monitor.

Frequently Asked Questions

How do I register for Microsoft SNDS?

Go to postmaster.live.com and sign in with a Microsoft account. Navigate to Smart Network Data Services and click 'Request Access.' You'll need to provide the IP addresses or ranges you want to monitor and verify that you're authorized to send from them. Approval typically takes 24–48 hours. Once approved, SNDS begins showing data for your IPs including message volume, spam trap hits, and filter verdicts. Also register for Microsoft's Junk Mail Reporting Program (JMRP) through the same portal to receive complaint notifications from Outlook users.

What does a Red status in Microsoft SNDS mean?

Red status in SNDS means Microsoft is blocking or heavily filtering your mail to Outlook.com, Hotmail, and Live.com recipients. This is triggered when your complaint rate from Microsoft users exceeds approximately 1% or when your sending IP hits Microsoft spam traps. Red status requires immediate action: stop sending from the affected IP, investigate the root cause (complaint spike, list quality issue, authentication failure), and submit a delisting request through Microsoft's Sender Support portal at sendersupport.olc.protection.outlook.com. Recovery from Red typically takes 24–72 hours after the underlying issue is resolved.

Is SNDS data available for my domain or just my IP?

SNDS primarily provides IP-level data — reputation verdicts, message volume, trap data, and complaint rates are all reported per sending IP address. Domain-level data for Microsoft is not exposed through SNDS in the same way Google Postmaster Tools shows domain reputation. For domain-specific Microsoft deliverability insights, monitor your DMARC aggregate reports for Outlook.com alignment data and use third-party sender reputation tools like Talos Intelligence, which provides domain-level reputation assessments used by many Microsoft partners.

Related Terms

Gmail Postmaster Tools

Google's free service that shows domain reputation, spam rate, authentication pass rates, and delivery errors for mail sent to Gmail. The most important warm-up monitoring tool.

IP Reputation

The trust score ISPs assign to a specific sending IP based on bounce rates, complaint rates, spam trap hits, and sending pattern consistency.

Domain Reputation

The permanent trust score ISPs assign to your sending domain based on historical behavior. Unlike IP reputation, a damaged domain reputation can take months to recover.

Complaint Rate (Spam Complaint Rate)

The percentage of recipients who click 'Mark as Spam.' Google's 2024 guidelines treat anything above 0.10% as a serious deliverability risk.

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