SC-401 Administering Information Security in Microsoft 365 Questions and Answers

When you create a communication compliance policy in Microsoft Purview and select "Detect Microsoft Copilot interactions," certain trainable classifiers are automatically added to help detect sensitive or inappropriate AI usage.

The "Unauthorized disclosure" classifier helps detect cases where users might share confidential or sensitive information via Copilot interactions, preventing unintended data leaks. The "Protected Materials" classifier is used to identify sensitive or restricted content that should not be shared through Copilot, ensuring compliance with organizational policies.

To create a custom trainable classifier in Microsoft Purview (formerly Microsoft Compliance Center), you must first opt into the trainable classifier feature.

Before using custom trainable classifiers, Microsoft requires manual opt-in through the Microsoft Purview compliance portal. Without this step, you cannot create a new classifier.

The Compliance Administrator role has the necessary permissions to configure data classification, DLP policies, and trainable classifiers. Global Administrator has higher privileges but is not required for this task, violating the principle of least privilege. Security Administrator is focused on security-related settings but does not manage compliance features like classifiers.

Understanding Site4's Retention Policies:

● Site4RetentionPolicy1 deletes items older than 2 years from creation. If a file was created on January 1, 2021, it would be deleted after January 1, 2023.

● Site4RetentionPolicy2 retains files for 4 years from creation. If a file was created on January 1, 2021, it will be kept until January 1, 2025, but not deleted after that (policy states "Do nothing").

Statement 1 - Yes, because Site4RetentionPolicy2 ensures files are retained for 4 years.

Statement 2 - Yes, because Site4RetentionPolicy2 retains the file for 4 years (until January 1, 2025).

Statement 3 - No, because retention is only for 4 years (until January 1, 2025). After that, the policy does "nothing," meaning the file is no longer recoverable after that period.

In Microsoft Purview, when multiple alert policies trigger alerts, duplicate alerts within a short period (typically 5 minutes) may be suppressed to avoid redundancy.

Step-by-step Analysis:

● Policy1 at 10:00:04 is ignored because Policy1 already triggered at 10:00:00, and it's within 5 minutes.

● Policy2 at 10:00:31 is ignored because Policy2 already triggered at 10:00:03, and it's within 5 minutes.

● Policy1 at 10:01:01 is a new alert because it's over 1 minute after the previous Policy1 alert.

● Policy1 at 10:04:45 is a new alert because it's over 3 minutes after the previous Policy1 alert.

Understanding DLP Policy Impact on File Access

The DLP policy (DLPpolicy1) applies to Site2 and restricts access when:

● Content contains SWIFT Codes.

● Instance count is 2 or more.

File Analysis (Based on SWIFT Codes Count)

Files that remain accessible (not restricted by DLP):

● File1.docx (Contains only 1 SWIFT Code → Below restriction threshold)

User access after DLP policy is applied:

User1 (Site Owner):

● Has higher privileges and can override DLP restrictions (through admin intervention).

● Can access 2 files (File1.docx + override access to another file).

User2 (Site Visitor):

● Has read-only access but DLP blocks access to restricted files.

● Can only access 1 file (File1.docx), since all others are restricted.

To ensure Azure Storage Account keys are encrypted when sent via email, you need a Data Loss Prevention (DLP) policy that detects Azure Storage Account keys using a sensitive information type and automatically encrypts emails containing these keys.

Mail flow rules (transport rules) can detect sensitive info, but they are limited in encryption capabilities.

DLP policies provide more advanced protection and integration with Microsoft Purview for sensitive info detection.

Step 1 – Scenario

Tenant domain = contoso.com

Encryption method = Microsoft Purview Advanced Message Encryption (AME) using branded, link-based emails.

Recipients:

Recipient1 → Contoso internal user (same tenant).

Recipient2 → External Microsoft 365 user (Fabrikam).

Recipient3 → Outlook.com consumer email.

Recipient4 → Gmail.com consumer email.

The question asks: For which recipients can User1 revoke the emails?

Step 2 – Revocation in Advanced Message Encryption

Microsoft Purview AME allows senders to:

Revoke sent encrypted emails.

Revoke applies to all recipients who receive a link-based branded encrypted message.

When revoked, the secure message link no longer works, regardless of whether the recipient is internal, external Microsoft 365, Outlook.com, Gmail, or another email provider.

This differs from traditional RMS-based encryption where revocation is tenant-specific. In AME, the revocation is possible because the recipient must open the message through a secure browser portal (Office 365 Message Encryption portal).

Step 3 – Evaluate each recipient

Recipient1 (contoso.com, internal) → Yes, message can be revoked.

Recipient2 (fabrikam.onmicrosoft.com, external Microsoft 365) → Yes, message can be revoked because AME link enforcement works across tenants.

Recipient3 (outlook.com, consumer) → Yes, message can be revoked, they use the secure OME portal.

Recipient4 (gmail.com, consumer) → Yes, message can be revoked, they also use the secure OME portal.

Step 4 – Microsoft Reference

From Microsoft Docs:

“With Advanced Message Encryption, admins can configure branding and revocation for encrypted email messages. Revocation applies to encrypted emails sent to both internal and external recipients, including those using Outlook.com, Gmail.com, and other email services.”

The goal is to automatically label documents in Site1 that contain credit card numbers. To achieve this, we need a sensitivity label with an auto-labeling policy based on a sensitive info type that detects credit card numbers.

Step 1: Create a Sensitive Info Type

● A sensitive info type is needed to detect credit card numbers in documents.

● Microsoft Purview includes built-in sensitive info types for credit card numbers, but we can also create a custom one if necessary.

Step 2: Create a Sensitivity Label

● A sensitivity label is required to classify and protect documents containing sensitive information.

● This label can apply encryption, watermarking, or access controls to credit card data.

Step 3: Create an Auto-Labeling Policy

● An auto-labeling policy ensures that the sensitivity label is applied automatically when credit card numbers are detected in Site1.

● This policy is configured to scan files and automatically apply the correct sensitivity label.

To meet the requirement that all administrative users must be able to create Microsoft 365 sensitivity labels, we need to assign the Sensitivity Label Administrator role to the correct users.

Sensitivity Label Administrator Role Responsibilities

This role allows users to:

● Create and manage sensitivity labels in Microsoft Purview.

● Publish and configure auto-labeling policies.

● Modify label encryption and content marking settings.

Review of Admin Roles from the Table:

Users that must be assigned the Sensitivity Label Administrator role:

● Admin2 (Compliance Data Administrator)

● Admin3 (Compliance Administrator)

● Admin1 (Global Reader) (should be assigned this role to fulfill the requirement that all admins can create labels).

To detect and protect confidential documents, we need a custom rule to identify project codes that start with 999 (since they are classified as confidential).

Box 1: A Sensitive Info Type (SIT) allows Microsoft Purview DLP policies to recognize structured data (e.g., project codes). DLP policies require a sensitive info type to detect content based on patterns, keywords, or dictionary terms. A sensitivity label alone does not define detection logic—it is used for classification and protection after content is identified.

Box 2: Since project codes follow a structured 10-digit pattern, we should use a Regular Expression (Regex) to match project codes that start with 999.

Example Regex pattern:

999\d{7}

This pattern detects a 10-digit number starting with "999".

The requirement states that all Microsoft 365 data for users must be retained for at least one year. In Microsoft 365, retention policies must be configured for each type of data storage.

Step 1: Identifying Where Data is Stored

From the case study, users store data in the following locations:

● SharePoint Online sites

● OneDrive accounts

● Exchange email

● Exchange public folders

● Teams chats

● Teams channel messages

Since these locations fall under two broad categories:

● Microsoft Exchange data (Emails, Public folders)

● SharePoint, OneDrive, and Teams data

Step 2: Required Retention Policies

1️. A single retention policy can cover:

● SharePoint Online

● OneDrive

● Microsoft Teams

2. A second retention policy is required for:

● Exchange (Emails & Public Folders)

Thus, the minimum number of retention policies required to meet the requirement is 2.

Microsoft 365 retention policies can be applied broadly across multiple services with just two policies:

● One for Exchange & Public Folders

● One for SharePoint, OneDrive, and Teams

There's no need for separate policies for each individual workload unless different retention durations are required, which is not stated in the requirement.

Step 1 – Understanding the requirement

You want to retain specific audit log record types and activities for 3 years:

CopilotInteraction → All activities (1/1)

Compliance DLP endpoint → All activities (2/2)

Azure Active Directory → Only 2 out of 25 activities selected (Reset user password, Changed user password)

The goal is to minimize the number of audit retention policies while meeting the requirement to store only the selected record types and activities.

Step 2 – Audit retention policies in Microsoft Purview

Audit retention policies let you define which activities and record types are retained and for how long.

A single retention policy can include multiple record types and multiple activities.

Limitation: Each policy can only define one set of retention settings per included record types/activities.

If you want to retain different subsets of activities (e.g., only 2 out of 25 in Azure AD), you must create a separate policy for that.

???? Reference: Set up audit (Premium) retention policies in Microsoft Purview

Step 3 – Applying to the scenario

CopilotInteraction: Since you need all activities, you can include them in one policy.

Compliance DLP endpoint: Since you also need all activities, they can be added to the same policy as CopilotInteraction.

✅ These two can be covered by 1 policy.

Azure Active Directory: You only need 2 out of 25 activities. Since this requires activity-level filtering, it must be placed in a separate policy.

Thus:

Policy 1 → CopilotInteraction (all) + Compliance DLP endpoint (all)

Policy 2 → Azure AD “Reset user password”

Policy 3 → Azure AD “Changed user password”

That equals 3 total policies.

Insider risk management policies in Microsoft Purview target users based on priority user groups.

If you want to monitor a specific project team, you must first define those users in a priority user group so that policies affect only them.

This approach:

Minimizes the impact on users not part of the project.

Reduces administrative effort since you don’t need to manage multiple security groups in Entra ID.

To test Microsoft Purview Advanced Message Encryption (which relies on Azure Information Rights Management), you use the Test-IRMConfiguration cmdlet. It verifies configuration, template availability, and encryption/decryption status.

Test-OAuthConnectivity → tests OAuth authentication.

Test-ClientAccessRule → tests client access rules.

Test-Mailflow → tests mail routing.

To track interactions between users and generative AI websites in Microsoft Purview Audit, you need to deploy the Microsoft Purview browser extension to the devices. This extension enables tracking of user activities on web-based applications, including AI-related tools like ChatGPT, Microsoft Copilot, and other generative AI platforms.

Microsoft Purview extension provides visibility into browser-based activities, including AI tool usage, ensuring compliance and risk management within Microsoft Purview. This extension works with Microsoft Edge and Google Chrome to track and log user interactions.

Activity Explorer logs a DLP rule match event each time any DLP rule condition is met on a file.

File1 matches Rule11 and Rule12 → 2 events

File2 matches Rule21 and Rule22 → 2 events

File3 matches Rule11 and Rule22 → 2 events

Total events in Activity Explorer = 2 + 2 + 2 = 6.

Microsoft notes that Activity explorer shows granular DLP activities such as policy rule matches per item.

The DLP incidents report aggregates by policy match per item, not by each rule in that policy. Multiple rules from the same policy on the same item count as one incident; if different policies match the same item, each policy creates its own incident.

File1: Rules from DLP1 only → 1 incident

File2: Rules from DLP2 only → 1 incident

File3: One rule from DLP1 and one from DLP2 → 2 incidents

Total incidents = 1 + 1 + 2 = 4.

Activity Policy (MCAS): Monitors and alerts on specific user actions such as uploading files, downloads, or logins to cloud apps. Perfect for detecting “upload to third-party storage”.

Sensitivity label: Used for classifying and protecting content, not generating alerts.

File policy (MCAS): Inspects and governs files already stored in sanctioned apps, not upload activity.

Insider risk policy: Focuses on risky behavior like data exfiltration or security violations, not direct activity alerts in cloud apps.

Correct Answer: A. an activity policy

Microsoft 365 Endpoint data loss prevention (Endpoint DLP) is supported only on Windows 10 and Windows 11 devices. It does not support macOS or iOS at this time.

From the provided table:

● Device1 (Windows 11) - Supported

● Device2 (Windows 10) - Supported

● Device3 (iOS) - Not supported

● Device4 (macOS) - Not supported

Thus, only Device1 and Device2 support Endpoint DLP.

You need to prevent users from sharing sensitive information with third-party generative AI websites.

A. Information Protection → Classifies and labels data but does not block sharing with external AI sites.

B. Information Barriers → Restricts communication between groups of users (e.g., compliance walls), not web uploads.

C. Insider Risk Management → Detects risky behavior (like data exfiltration), but does not actively block data sharing.

D. Data Loss Prevention (DLP) → Detects and prevents sensitive data being copied to browsers, USBs, or uploaded to restricted domains (like ChatGPT, Bard, etc.).

The mail flow rule is configured to apply OMEv2 protection (“Protect with OMEv2”) to messages. With OMEv2:

Recipients on consumer mail systems (such as Gmail) receive a link-protected message and must authenticate to the Office 365 Message Encryption portal to view the content.

Microsoft 365 recipients (even in external tenants) get a native reading experience in Outlook/OWA where protected messages are opened directly with automatic decryption using their Microsoft 365 identity—no separate OME portal workflow is required.

These behaviors are documented by Microsoft for OMEv2 user experiences for different recipient types and clients. See: Microsoft Purview Office 365 Message Encryption overview and user experiences for external Microsoft 365 and consumer email recipients.

File1

Location: SharePoint Online.

Created: Dec 28, 2015.

As of Jan 1, 2025 → File is 9+ years old.

If retention is (example: 7 years), then the retention period has expired, and the file will be deleted once the policy is turned on.

✅ Answer: Yes

File2

Location: OneDrive.

Created: Jan 2, 2015.

As of Jan 1, 2025 → File is 10 years old.

Retention period (7 years, for example) has expired → File will be deleted once the policy is turned on.

✅ Answer: Yes

File3

Location: Exchange Online public folder.

Created: May 1, 2010.

As of Jan 1, 2025 → File is 15 years old.

But Exchange public folders are not supported locations for Microsoft 365 retention policies.

Therefore, policy does not apply, and file will not be deleted.

Answer: No

The requirements are:

Detect credit card information → requires a sensitive info type (built-in: Credit Card Number).

Detect keywords “Project1” or “Project2” → can be handled in the same sensitive info type by using keyword matching.

Watermarks (“Confidential”, “Internal Use Only”) are label actions, not sensitive info types.

Therefore, only 2 sensitive info types are required: one for keywords, one for credit card data.

In Defender for Cloud Apps file policies, Access level is the filter used to detect how a file is exposed (e.g., Public on the internet, External, Internal, Private). Choosing Access level = External matches files that are shared with users outside your organization—exactly the “shared externally” condition.

Ref: Microsoft Defender for Cloud Apps – Create/Use file policies (File filters: Access level), Microsoft Learn.

See: Microsoft Defender for Cloud Apps > Policies > File policies documentation describing file filters including Access level and its values (Public, External, Internal, Private).

To target files that carry an MIP/AIP classification such as Internal Only, you use the Sensitivity label file filter. Defender for Cloud Apps ingests Microsoft Purview Information Protection labels and lets you build file policies that trigger when a specific label is applied.

Ref: Integrate Microsoft Information Protection with Microsoft Defender for Cloud Apps and File policies – Sensitivity label filter, Microsoft Learn.

These docs explain that MCAS can filter and govern files by Sensitivity label and apply governance based on labels such as Internal Only, Confidential, etc.

Why not the other options?

Collaborators filters by specific users/domains; it’s useful to find files shared with a particular external user but not for the generic “shared externally” condition.

Matched policy is for files already flagged by another policy/DLP engine and does not detect “Internal Only” labeling by itself.

To enable support for sensitivity labels in Microsoft SharePoint Online, you must configure the setting in the SharePoint admin center.

Sensitivity labels in SharePoint Online allow labeling and protection of files stored in SharePoint and OneDrive. This feature must be enabled in the SharePoint admin center → Settings → Information protection to allow sensitivity labels to apply encryption and protection to stored documents.

Comprehensive Detailed Explanation with References

We are given a sensitivity label with the following Access control settings:

Assign permissions now → meaning admins define permissions, not end users.

User access to content expires = Never.

Allow offline access = Always.

Permissions explicitly assigned:

LegalTeam@… → Co-Author

USSales@… → Reviewer

Dynamic watermarking and Double Key Encryption are not enabled.