Microsoft SNDS: How to Use Smart Network Data Services
The short answer
Microsoft Smart Network Data Services (SNDS) is a free Outlook.com tool that shows per-IP sending data — traffic, complaint rate and filter results — for IPs you control. Sign in with a Microsoft account, request access to your IPs, then read the daily Data report to see why Outlook.com is filtering your mail.
How to use Microsoft SNDS: get access to Smart Network Data Services, read per-IP complaint and filter data, and pair it with the Junk Email Reporting loop.
On this page
- 01What SNDS shows you
- 02Before you start: who SNDS actually helps
- 03How to get SNDS access, step by step
- 04What the SNDS data colours mean
- 05Pair SNDS with the Junk Email Reporting Program
- 06SNDS and the other providers' sender tools
- 07What to do when SNDS does not explain it
- 08Where AI Emaily fits, and where it does not
If your mail keeps landing in the Outlook.com, Hotmail or Live.com junk folder, Microsoft Smart Network Data Services (SNDS) is the free tool that tells you why. This guide covers how to use Microsoft SNDS end to end: getting access, reading the per-IP data, and pairing it with the Junk Email Reporting Program feedback loop.
One thing to settle before you start: SNDS is built around sending IP addresses, not domains or accounts. It helps the people who control their own sending IPs. If you send through a shared pool you do not control, most of what follows is someone else's job — and this post is honest about who that is.
What SNDS shows you#
SNDS is Microsoft's postmaster service for its consumer mailboxes — Outlook.com, Hotmail and Live.com. For each IP you are authorised to see, it publishes a daily Data report describing how Outlook.com treated the mail that IP sent.
The report is diagnostic, not a control panel. You cannot change filtering from inside SNDS. What you get is evidence: how much you sent, how many recipients marked it as junk, and how Outlook.com is currently filtering the IP.
| Data report column | What it tells you |
|---|---|
| Activity period / date | The day the traffic was seen, with a start time. The report refreshes daily. |
| Message counts (RCPT / DATA) | How many recipients the IP attempted and how many messages it delivered to Outlook.com that day. |
| Complaint rate | The share of delivered mail that recipients marked as junk. Lower is better; Microsoft does not publish one fixed pass/fail number, so treat any rise as a warning. |
| Filter result | A colour showing how Outlook.com is treating the IP right now — the colours are explained further down. |
| Sample HELO / MAIL FROM | Example values the IP presented, useful for spotting a compromised host or an unexpected sender using your IP. |
Spam-trap counts were removed in July 2026
Before you start: who SNDS actually helps#
SNDS authorises access per IP, and Microsoft only lets you see IPs you are responsible for. So the tool is useful in exact proportion to how much control you have over your sending infrastructure.
If you run your own mail server or rent a dedicated IP, SNDS is squarely for you. If you send through a large shared pool — a typical marketing platform, or a hosted mailbox on Microsoft 365 or Google Workspace — you usually do not control that IP, and the provider is the party who can enrol it and read the data.
| Your sending setup | Can you enrol the IP in SNDS? | Who monitors the reputation |
|---|---|---|
| Own mail server / dedicated IP | Yes — you control the IP and can pass the authorisation check | You |
| ESP with a dedicated-IP option | Usually — if the provider assigns you the IP and supports SNDS | You, with the provider |
| Shared ESP or marketing pool | Rarely — the IP is shared, so the provider holds authorisation | The provider |
| Microsoft 365 hosted mailbox | No — outbound uses Microsoft's shared IPs | Microsoft |
| Google Workspace mailbox | No — outbound uses Google's IPs; use Google Postmaster Tools instead |
How to get SNDS access, step by step#
Getting Microsoft Smart Network Data Services access is a short, one-time process. You sign in, tell Microsoft which IPs are yours, and prove it.
- 1
Sign in with a Microsoft account
Open the SNDS site from the Outlook.com Postmaster pages and sign in with any Microsoft account. You do not need an Outlook.com mailbox of your own to use the tool.
- 2
Request access to your IPs
Under Request Access, enter the IP addresses or CIDR ranges you send from. You can list a single IP or a network block that you own.
- 3
Complete the authorisation check
Microsoft verifies you are responsible for the IPs. For a range it typically emails the contact listed for that network, or lets the block owner approve requests for sub-ranges. Approve the request to unlock the data.
- 4
Wait for the data to populate
Once approved, the Data report fills in over the following days as the IP sends to Outlook.com. An IP with little or no recent traffic will show little or nothing.
- 5
Read the Data and IP Status views
Open the Data report for per-day detail, and the IP Status view for a quick read on any IP that has been flagged as blocked or rate-limited.
What the SNDS data colours mean#
The Filter Result is colour-coded so you can read reputation at a glance. Treat it as a traffic light for the IP.
- Green — Outlook.com is accepting the IP's mail normally, with little filtering. This is where you want to stay.
- Yellow — a meaningful share is being sent to the junk folder or slowed down. Read it as an early warning and look hard at what changed.
- Red — most or all of the IP's mail is being junked or blocked. Sending should stop until the underlying cause is fixed, or the reputation will keep sinking.
Do not chase a third-party number
Pair SNDS with the Junk Email Reporting Program#
SNDS tells you the complaint rate. The Junk Email Reporting Program (JMRP) tells you which messages drew the complaints. Together they turn a number into something you can act on.
JMRP is Microsoft's feedback loop for Outlook.com. When an Outlook.com user marks one of your messages as junk, Microsoft forwards a copy of that message to an address you nominate, so you can see exactly what was reported and suppress that recipient.
Enrol from the same Outlook.com Postmaster pages: sign in, submit the IP ranges you send from and the address that should receive the complaint copies, then complete Microsoft's review. Once it is live, complaints arrive as they happen. For monitoring at scale, SNDS also offers Automated Data Access, which lets an approved account pull the same report from a URL with a key.
Feed complaints straight into suppression
SNDS and the other providers' sender tools#
Outlook.com is one mailbox provider. If your mail also lands in Gmail or Yahoo junk, SNDS will not tell you why — each provider runs its own tool and its own rules. Use them side by side, and note that they key on different things: SNDS is built around the sending IP, while Google's tool is built around the sending domain.
| Provider | Tool | What it keys on |
|---|---|---|
| Outlook.com / Hotmail / Live | SNDS + Junk Email Reporting Program | Sending IP |
| Gmail | Google Postmaster Tools | Sending domain |
| Yahoo / AOL | Yahoo Sender Hub + complaint feedback loop | Domain and IP |
What to do when SNDS does not explain it#
SNDS shows reputation, not root cause. A red IP with a low complaint rate usually means an authentication or content problem, not angry recipients. When the data does not add up, move to Microsoft's authentication troubleshooting.
Most Outlook.com filtering traces back to SPF, DKIM or DMARC. Microsoft's guidance is to open a message that got junked, read its Authentication-Results header, and work from what failed:
- SPF fail or softfail — the sending IP is not listed in your domain's SPF record. Add it, and keep the record under the 10-DNS-lookup limit.
- DKIM fail — the signature did not verify, often because a gateway modified the message body after signing, or the required CNAME records were never published.
- DMARC fail on alignment — SPF or DKIM passed, but for a domain that does not match your From address. Enabling DKIM signing for the From domain gives DMARC the aligned pass it needs.
- A rejection code such as 550 5.7.23 or 550 5.7.1 — the message was refused on authentication, not filtered. Fix the record the code points to.
Microsoft's own Remote Connectivity Analyzer and its message-header analyzer let you test SPF, DKIM and DMARC and read the results without guessing — both are linked in the Sources below. Fix the authentication first; a clean SPF, DKIM and DMARC setup is what turns a yellow SNDS reading back to green over the following days.
Where AI Emaily fits, and where it does not#
To be plain about our own tool: AI Emaily is a mail client, not a deliverability or sender-reputation service. It does not monitor sending IPs, it will not replace SNDS, and if your job is bulk sending, SNDS plus your ESP own that problem. We build AI Emaily, and we would rather say that than imply a fit that is not there.
Where it is genuinely adjacent: SNDS lives on the sending side, and AI Emaily lives on the receiving and managing side. It connects your Outlook.com, Microsoft 365, Gmail or IMAP mailbox and handles the inbound flow — triaging what arrives, drafting replies in a voice you set, and keeping junk mail and phishing out of the inbox. If you also run a busy Outlook mailbox day to day, that is the part we help with.
Frequently asked
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Written by
Nafiul HasanNafiul Hasan is an entrepreneur and AI automation system builder with 10+ years of experience turning messy, manual workflows into reliable automated systems. He designs and ships AI enterprise solutions end-to-end — the agent logic, the data plumbing, and the product people actually use — and founded AI Emaily to give busy professionals their attention back. He writes here from the builder's seat: what works, what breaks, and how to put AI to work without giving up control.