Microsoft 365 Data Security Engineering

Make your organization's data defensible

Most tenants have Purview licensed and nothing configured, or configured badly by someone who has left. This course teaches the discipline end to end: know what is sensitive, mark it so every control downstream can act on it, close the channels it actually leaves through, keep what must be kept, watch the people who already have legitimate access, and answer what left, when, and who moved it. Aligned to the SC-401 skills measured, and built to teach the job rather than the exam.

Included with Premium, from $19.99/month, or $179/year and save 25%. Preview the first module free, no account needed.
Your subscription also includes the Practice Hub: graded scenarios, forensic cases, query drills and the response playbooks.
View Pricing Take End of Course Exam → 40 CPE Credits

What you'll be able to do

✓Stand up a complete data security program in a Purview tenant that has the licenses and nothing configured, from classification through to the AI-readiness controls
✓Build classification that identifies controlled data to a measured recall, with custom sensitive information types, Exact Data Match, and trainable classifiers
✓Label and protect data so encryption and marking travel with it, and apply the label at scale with auto-labeling
✓Close the channels data leaves through with DLP and Endpoint DLP across mail, sites, and the device, and prove the block in simulation before it enforces
✓Set retention that keeps records for their term and disposes of them on schedule, and watch cleared insiders with Insider Risk Management and Adaptive Protection
✓Investigate a controlled-data exfiltration end to end with the Purview forensic trail, and keep a copilot from surfacing controlled data with DSPM for AI and DLP for Copilot
ARC403 | Premium tier | 12 modules across 6 phases | 36-40 hours at your own pace | 40 CPE credits | Lab optional

Course Syllabus

Every module and every lesson. The first three modules are open; the rest open on a click.

Download the full syllabus (PDF)

Course Orientation

Module 0Course OrientationCourse Preview

What this course teaches: how to build data security in a Purview tenant that has the license and none of the configuration. Classify what the business holds, label it so every control downstream can act, close the channels data leaves through, keep what must be kept, watch the people who already have access, and prove any of it worked. Start here.

Show 7 lessonsHide lessons
  1. 0.10.1 What Data Security Engineering IsPreview
  2. 0.20.2 The Purview SurfacePreview
  3. 0.30.3 How This Course Is StructuredPreview
  4. 0.40.4 Where This Shows UpPreview
  5. 0.50.5 What Purview Cannot DoPreview
  6. 0.60.6 Following AlongPreview
  7. 0.7Module SummaryPreview

Phase 1: Know your data

Module 1The Data Security Problem

Why data security is a different job: data has three states and a control that works in one does nothing in the others. Purview as a control plane over data at rest, in use and in motion. The E3 and E5 boundary stated once, properly. And least privilege for a data security team.

Show 12 lessonsHide lessons
  1. 1.11.1 The Three States of Data
  2. 1.21.2 A Document Is a Population
  3. 1.31.3 Purview as a Control Plane
  4. 1.41.4 The Classification Engine
  5. 1.51.5 Licensing: Capabilities, Not Features
  6. 1.61.6 The Boundary
  7. 1.71.7 The Compliance Role Groups
  8. 1.81.8 Least Privilege When the Privilege Is Reading Everything
  9. 1.91.9 The Global Admin Anti-Pattern
  10. 1.101.10 What a Program Actually Is
  11. 1.11Module Summary
  12. 1.12Check My Knowledge
Module 2Classification

Classification is the datum every other Purview control resolves to. Ten sections on sensitive information types, the confidence model, custom SITs, document fingerprinting, Exact Data Match, trainable classifiers, OCR, and the explorers that measure whether any of it worked. Build a classifier, measure its false-positive rate against real content, and tune it on evidence rather than instinct.

Show 12 lessonsHide lessons
  1. 2.12.1 Sensitive Information Types and the Confidence Model
  2. 2.22.2 Building a Custom SIT and Proving It Works
  3. 2.32.3 Document Fingerprinting
  4. 2.42.4 Exact Data Match: The Schema
  5. 2.52.5 Exact Data Match: Hashing, Upload, and Refresh
  6. 2.62.6 Trainable Classifiers
  7. 2.72.7 OCR and What It Cannot Read
  8. 2.82.8 Data Explorer and Content Explorer
  9. 2.92.9 Measuring and Tuning Classification
  10. 2.102.10 The Classification Decision
  11. 2.11Module Summary
  12. 2.12Check My Knowledge

Phase 2: Mark your data

Module 3Sensitivity Labels

The label is the only control that leaves your tenant. Taxonomy first, because the fourteen-label failure is organizational rather than technical, then the mechanics: scope, marking, encryption, publishing, and precedence.

Show 12 lessonsHide lessons
  1. 3.13.1 The Label That Travels
  2. 3.23.2 The Fourteen-Label Failure
  3. 3.33.3 Designing a Taxonomy
  4. 3.43.4 Label Scope
  5. 3.53.5 Content Marking
  6. 3.63.6 Encryption: What It Actually Does
  7. 3.73.7 The Encryption Trade
  8. 3.83.8 Publishing
  9. 3.93.9 Priority and Precedence
  10. 3.103.10 The Taxonomy Decision
  11. 3.11Module Summary
  12. 3.12Check My Knowledge

Phase 3: Stop it leaving

Module 6DLP Policy Design

Design a DLP policy from a requirement, not a template. Locations, conditions, actions, overrides. Rule and policy precedence with a worked collision. Simulation to audit to block, and why that order is the only safe one.

Show 12 lessonsHide lessons
  1. 6.16.1 Requirements to Policy
  2. 6.26.2 Locations
  3. 6.36.3 Conditions
  4. 6.46.4 Actions
  5. 6.56.5 Overrides and Notifications
  6. 6.66.6 Roles and Permissions
  7. 6.76.7 Rule Precedence
  8. 6.86.8 Policy Precedence
  9. 6.96.9 Simulation to Block
  10. 6.106.10 File Policies in Cloud Apps
  11. 6.11Module Summary
  12. 6.12Check My Knowledge

Phase 4: Keep and dispose

Module 8Retention and Records

Retention as a two-sided obligation: keep content as long as it must be kept, and dispose of it deliberately when the obligation ends. Labels against policies, adaptive scopes, precedence taught with a worked conflict, recovery, disposition review, and the records-management boundary.

Show 12 lessonsHide lessons
  1. 8.18.1 Retention Is Two Obligations
  2. 8.28.2 Labels vs Policies
  3. 8.38.3 What Retention Does to an Item
  4. 8.48.4 Static and Adaptive Scopes
  5. 8.58.5 Publishing and Auto-Apply
  6. 8.68.6 Precedence: The Four Principles
  7. 8.78.7 A Worked Conflict and Policy Lookup
  8. 8.88.8 Recovering Retained Content
  9. 8.98.9 Disposition and Review
  10. 8.108.10 The Records Management Boundary
  11. 8.11Module Summary
  12. 8.12Check My Knowledge

Phase 5: Watch and investigate

Module 9Insider Risk Management

Watching the people who handle your data, powerfully and lawfully. The triggering-event gate, the role groups and separation of duties, the privacy model, the HR connector, signal sources and the endpoint, thresholds, forensic evidence, Adaptive Protection, and the path from alert to a preserved, escalated case.

Show 12 lessonsHide lessons
  1. 9.19.1 What Insider Risk Management Is
  2. 9.29.2 Roles, Permissions, and Separation of Duties
  3. 9.39.3 The Privacy Model
  4. 9.49.4 Connectors and the HR Connector
  5. 9.59.5 Signal Sources and the Endpoint
  6. 9.69.6 Templates, Indicators, and Thresholds
  7. 9.79.7 Forensic Evidence Settings
  8. 9.89.8 Adaptive Protection
  9. 9.99.9 Alerts, Cases, and Notices
  10. 9.109.10 Standing Up Insider Risk Management for Northgate
  11. 9.11Module Summary
  12. 9.12Check My Knowledge
Module 10Investigation

The data-security engineer as investigator. Purview Audit Standard against Premium and the audit-log retention gap that ends investigations, searching the audit log, Activity Explorer as the label and DLP trail, responding to DLP alerts in Purview and in Defender XDR, Cloud Apps file-policy alerts, Content Search for what was in it, and correlating the Purview finding against endpoint and cloud telemetry.

Show 12 lessonsHide lessons
  1. 10.110.1 The Engineer as Investigator
  2. 10.210.2 Purview Audit: Standard and Premium
  3. 10.310.3 Audit Retention and the Gap That Ends Investigations
  4. 10.410.4 Searching the Unified Audit Log
  5. 10.510.5 Activity Explorer: The Label and DLP Trail
  6. 10.610.6 Responding to DLP Alerts
  7. 10.710.7 Purview Alerts in Defender XDR
  8. 10.810.8 Cloud App File and Activity Alerts
  9. 10.910.9 Content Search: Collecting the Evidence
  10. 10.1010.10 Correlating Endpoint and Cloud
  11. 10.11Module Summary
  12. 10.12Check My Knowledge

Phase 6: AI and configuration guides

Module 11Data Security for AI

Securing data for AI in Microsoft Purview. Why a copilot turns survivable oversharing into exposure, DSPM for AI as the front door, its prerequisites and roles, data risk assessments, sensitivity labels and DLP for Microsoft 365 Copilot, the oversharing controls in SharePoint, third-party AI and endpoint controls, prompt and response governance, and assembling a Copilot readiness baseline.

Show 12 lessonsHide lessons
  1. 11.111.1 Why AI Changes the Data Security Problem
  2. 11.211.2 DSPM for AI: The Front Door
  3. 11.311.3 Prerequisites and Onboarding
  4. 11.411.4 Data Risk Assessments and Oversharing
  5. 11.511.5 Sensitivity Labels as the Copilot Control
  6. 11.611.6 DLP for Microsoft 365 Copilot
  7. 11.711.7 Oversharing Controls in SharePoint
  8. 11.811.8 Third-Party AI and the Endpoint
  9. 11.911.9 Prompt and Response Governance
  10. 11.1011.10 The Copilot Readiness Baseline
  11. 11.11Module Summary
  12. 11.12Check My Knowledge
Module 12Configuration Guides

Step-by-step configuration guides for every control in the data-security program. Follow each guide in your own tenant to build classification, sensitivity labels and auto-labeling, DLP and endpoint DLP, retention, insider risk with Adaptive Protection, and the AI-readiness controls, with the portal paths, the PowerShell, the verification, and the pitfalls.

Show 6 lessonsHide lessons
  1. 12.112.1 Classification: Custom SITs and Exact Data Match
  2. 12.212.2 Sensitivity Labels and Auto-labeling
  3. 12.312.3 DLP and Endpoint DLP
  4. 12.412.4 Retention and Records
  5. 12.512.5 Insider Risk and Adaptive Protection
  6. 12.612.6 Data Security for AI

Phase 0: Course Resources

ResourcesCookbooks

Ordered procedures for the data security work that recurs: standing up classification, rolling out labels, deploying DLP without stopping the business.

Show 7 lessonsHide lessons
  1. 1Rolling Out Sensitivity Labels
  2. 2Deploying DLP Without Stopping the Business
  3. 3Getting Ready for Copilot
  4. 4Building a Classifier That Works
  5. 5Responding to a Data Incident
  6. 6Designing Retention That Deletes
  7. 7Standing Up Insider Risk
ResourcesLab Setup

Building a tenant with content messy enough to behave like a real estate, where you can watch a control cover nothing.

Show 5 lessonsHide lessons
  1. 1The Tenant and What It Carries
  2. 2Planting Content That Misbehaves
  3. 3Deploying Controls and Watching Them Miss
  4. 4Breaking It on Purpose
  5. 5Verify, Delays, and What the Lab Cannot Teach
ResourcesWalkthroughs

Data security work reasoned end to end, including the cases where the control was already there and the ones that end in doing nothing.

Show 6 lessonsHide lessons
  1. 1The DLP Number That Meant Nothing
  2. 2The Copilot Deadline
  3. 3The Encryption Request That Should Be Refused
  4. 4The Exfiltration That Was a Backup
  5. 5The Policy That Protected Nothing
  6. 6The Deletion That Never Happened
ResourcesPlaybooks

What to do when something fires or somebody asks: a DLP alert, a suspected leak, a subject access request, a regulator, a control that broke the business.

Show 7 lessonsHide lessons
  1. 1A DLP Alert Fires
  2. 2Content Has Left and Somebody Knows
  3. 3A Subject Access or Deletion Request
  4. 4A Control Has Broken the Business
  5. 5A Regulator or Auditor Asks
  6. 6Somebody Is Leaving With Access
  7. 7Somebody Found Content They Should Not See
ResourcesPlayground

Every practice surface available for this course, what each one gives you, and where the gaps are.

ResourcesReferences & Further Reading

Microsoft Purview documentation, Microsoft security documentation, sensitive information type and EDM references, DLP and endpoint guidance, retention and records, insider risk, DSPM for AI, and the frameworks and standards used throughout the course.

Show 1 lessonHide lessons
  1. 1DS100.1 References & Further Reading

Course Completion

CompletionCourse Exam

Microsoft 365 Data Security Engineering end-of-course exam: a simulation-based assessment testing whether you can scope a data security incident, establish what a label and a policy actually did, and respond without breaking the business process that produced the data.

Show 1 lessonHide lessons
  1. 1Course Completion. Microsoft 365 Data Security Engineering

Course overview

Data security engineering is its own discipline. It is not identity security with different portals, and it is not a compliance project with a dashboard at the end. The question every control in Purview resolves to is whether a classifier matched, and almost nobody measures whether theirs did. This course follows one organization's data from unknown to defended, and teaches you to prove each control works rather than assume it. Learn how to:

✓ Build a classification scheme that matches what the business holds, and measure its false-positive rate against real content
✓ Design a sensitivity label taxonomy that survives contact with users, and apply it without depending on them
✓ Write DLP policies that block the paths data actually leaves through, and roll them out without breaking Monday morning
✓ Set retention that satisfies the regulator without hoarding, and read the precedence rules before they surprise you
✓ Run insider risk without producing four hundred alerts a week, and investigate a case from the platform's own evidence

By the end you can walk into a licensed, unconfigured tenant and stand up a program you can defend, including an honest statement of what it does not cover.

How this course works

Data security in Microsoft 365 is a chain, and every link is inert without the one before it. This course runs it in the order it has to work.

1. Classify before you protect. Every Purview control resolves to a classification. Labels, DLP and retention all ask the same question first, and an estate that never answered it cannot enforce anything.

2. Label so the protection travels. A sensitivity label carries its protection out of the tenant with the file. That is the difference between a control and a boundary.

3. Automate the labeling, because users will not. Manual classification at scale is a policy nobody follows. Auto-labeling is what makes coverage real.

4. Write DLP against what actually leaves. Policy tuned against a hypothesis blocks legitimate work and misses the path in use. Run in simulation and read the result first.

5. Investigate what the controls reported. Alerts, insider risk signals and the audit record, read as an investigation rather than a queue.

The course closes with configuration guides for every control it built.

What this course assumes

No minimum experience and no prerequisite course. The Purview surface, the classification model and the licensing that gates each control are introduced where they first matter.

What makes it go faster: a tenant with the relevant Purview licensing, since much of this is gated. Not required, and the course is explicit about which control needs which tier.

What this course does not cover: incident response process, identity security and endpoint engineering, which are separate courses. This is protecting the data itself.

Who this course is for

You are a security engineer, M365 administrator, SOC analyst, or consultant with Purview in the tenant and a gap between what it could do and what it does. This course is designed for you if you want to:

✓ Move from "we have E5 so we have data protection" to naming which data is sensitive and proving it is labeled
✓ Deploy controls you can measure, rather than dashboards that look clean because nothing is firing
✓ Understand the licensing boundary properly, so you know what you can build on E3 today and what E5 actually buys
✓ Handle the newest half of the job, where a copilot indexes the oversharing that was survivable while discovery was hard

Compliance and privacy staff who need to know what the technical controls actually do belong here too. Every concept is taught at first use.

What you'll learn

By the end of this course you will be able to:

✓ Build custom sensitive information types, document fingerprints, Exact Data Match, and trainable classifiers, and choose correctly between them
✓ Obtain a false-positive rate from real content and tune a classifier on evidence rather than on the last complaint
✓ Design a label taxonomy, publish it, and auto-apply it client-side and service-side, including container labels
✓ Protect data beyond the tenant with the Information Protection client, the on-premises scanner, and message encryption
✓ Take DLP from requirements to policy, resolve rule precedence, and roll out simulation to audit to block in the only safe order
✓ Deploy endpoint DLP across the real channels: USB, cloud sync, print, clipboard, unallowed apps, and network shares
✓ Configure retention labels and policies, adaptive scopes, and precedence, and recover retained content
✓ Run insider risk management with its privacy model, connectors, and thresholds, and drive DLP enforcement from risk level
✓ Investigate with Purview Audit, Activity explorer, and Content Search, and close the audit retention gap before it ends a case
✓ Secure data for AI with DSPM for AI, prompt and response governance, and Copilot readiness as a data security exercise

Key course takeaways

✓ Stand up a complete data security program in a tenant that has Purview licensed and nothing configured
✓ Measure every control you deploy, because in classification wrong is quiet and a clean dashboard proves nothing
✓ Make the licensing call honestly, control by control, on E3 or E5
✓ Write the coverage statement that names its own edges before an auditor finds them
✓ Follow step-by-step configuration guides to build each control (classification, labels, DLP, retention, insider risk, and AI) in your own tenant

Things you need to know

What are the prerequisites for this course?

Familiarity with Microsoft 365 as an administrator or a user, and comfort reading a PowerShell cmdlet. No prior Purview, KQL, or compliance experience is required. Each is taught at first use and the content is self-contained.

What are the lab requirements?

None. The course is completable without a tenant. If you want to build every control as you learn it, a Microsoft 365 E5 trial or a developer tenant is enough, and the course states plainly which controls need E5 and which are reachable on E3. There is no lab image to download and no hypervisor to run.

How will the course benefit your career?

Purview is licensed in most Microsoft-shop enterprises and configured properly in very few of them. An engineer who can classify an estate, prove the classifiers work, close the exfiltration channels, and hand over a case file is answering the question boards have started asking. The AI half of the discipline is newer still, and the people who can do it are fewer.

Usage rights and disclaimer

Course materials: Licensed for individual professional development. You may not redistribute course content or share account credentials.

Fictional environment: All scenarios use Northgate Engineering. Any resemblance to real organizations is coincidental.

COURSE ASSESSMENT

End of Course Exam

Complete the course, then prove your skills under time pressure. Pass mark: 70. Earn your certificate with CPE credits.

40minutes
3phases
100points
1scenario
Take End of Course Exam

One random scenario per attempt. Certificate issued on pass.