Teams Private Channels Reengineered: Compliance & Data Security Actions Needed by Sept 20, 2025
You may have missed this critical update, as it was published only on the Microsoft Teams blog and flagged as a Teams change in the Message Center under MC1134737. However, it represents a complete reengineering of how private channel data is stored and managed, with direct implications for Microsoft Purview compliance policies, including eDiscovery, Legal Hold, Data Loss Prevention (DLP), and Retention. 🔗 Read the official blog post here New enhancements in Private Channels in Microsoft Teams unlock their full potential | Microsoft Community Hub What’s Changing? A Shift from User to Group Mailboxes Historically, private channel data was stored in individual user mailboxes, requiring compliance and security policies to be scoped at the user level. Starting September 20, 2025, Microsoft is reengineering this model: Private channels will now use dedicated group mailboxes tied to the team’s Microsoft 365 group. Compliance and security policies must be applied to the team’s Microsoft 365 group, not just individual users. Existing user-level policies will not govern new private channel data post-migration. This change aligns private channels with how shared channels are managed, streamlining policy enforcement but requiring manual updates to ensure coverage. Why This Matters for Data Security and Compliance Admins If your organization uses Microsoft Purview for: eDiscovery Legal Hold Data Loss Prevention (DLP) Retention Policies You must review and update your Purview eDiscovery and legal holds, DLP, and retention policies. Without action, new private channel data may fall outside existing policy coverage, especially if your current policies are not already scoped to the team’s group. This could lead to significant data security, governance and legal risks. Action Required by September 20, 2025 Before migration begins: Review all Purview policies related to private channels. Apply policies to the team’s Microsoft 365 group to ensure continuity. Update eDiscovery searches to include both user and group mailboxes. Modify DLP scopes to include the team’s group. Align retention policies with the team’s group settings. Migration will begin in late September and continue through December 2025. A PowerShell command will be released to help track migration progress per tenant. Migration Timeline Migration begins September 20, 2025, and continues through December 2025. Migration timing may vary by tenant. A PowerShell command will be released to help track migration status. I recommend keeping track of any additional announcements in the message center.
Alert on DLP Policy Change
Is it possible to configure an alert from Purview when a DLP policy is created, amended or removed? I am trying to build a process to satisfy NIST CM-6(2): Respond to Unauthorized Changes that identifies when a policy chnage happens and to cross reference to an authorised change record. I can find the events Updated, Created or Changed a DLP Poloicy in audit search but can Purview be configured to generate an alert when these events happen?Purview Webinars
REGISTER FOR ALL WEBINARS HERE Upcoming Microsoft Purview Webinars JULY 15 (8:00 AM) Microsoft Purview | How to Improve Copilot Responses Using Microsoft Purview Data Lifecycle Management Join our non-technical webinar and hear the unique, real life case study of how a large global energy company successfully implemented Microsoft automated retention and deletion across the entire M365 landscape. You will learn how the company used Microsoft Purview Data Lifecyle Management to achieve a step up in information governance and retention management across a complex matrix organization. Paving the way for the safe introduction of Gen AI tools such as Microsoft Copilot. 2025 Past Recordings JUNE 10 Unlock the Power of Data Security Investigations with Microsoft Purview MAY 8 Data Security - Insider Threats: Are They Real? MAY 7 Data Security - What's New in DLP? MAY 6 What's New in MIP? APR 22 eDiscovery New User Experience and Retirement of Classic MAR 19 Unlocking the Power of Microsoft Purview for ChatGPT Enterprise MAR 18 Inheriting Sensitivity Labels from Shared Files to Teams Meetings MAR 12 Microsoft Purview AMA - Data Security, Compliance, and Governance JAN 8 Microsoft Purview AMA | Blog Post 📺 Subscribe to our Microsoft Security Community YouTube channel for ALL Microsoft Security webinar recordings, and more!
Restrict sharing of Power BI Data to limited users
In the Power BI admin center, we have enabled the setting: "Restrict content with protected labels from being shared via link with everyone in your organization". As expected, this prevents users from generating "People in your organization" sharing links for content protected with sensitivity labels. We only have one sensitivity label with protection enabled. However, due to Power BI’s limitations with labels that include "Do Not Forward" or user-defined permissions, this label is not usable in Power BI. Our Power BI team wants to restrict sensitive data from being shared org-wide and instead limit access to specific individuals. One idea was to create another sensitivity label with encryption that works with Power BI and use that to enforce the restriction. However, such a label would also affect other Microsoft 365 apps like Word, Excel, and Outlook — which we want to avoid. I looked into using DLP, but MS documentation mentions below limitations, that makes me unsure if this will meet the requirement. 1. DLP either restricts access to the data owner or to the entire organization. 2. DLP rules apply to workspaces, not individual dashboards or reports. My question: Is there any way to restrict sharing of Power BI (or Fabric) content to specific users within the organization without changing our existing sensitivity label configurations or creating a new encryption-enabled label that could impact other apps?Microsoft 365 Copilot not showing up as location in DLP
Hi, I am working on implementing security measures for Microsoft Copilot in a client environment. I want to create a DLP policy to not process data with certain sensitivity labels but when I go into DLP to create the policy, the location for Microsoft 365 Copilot is not an option. I also noticed that the "Fabric and Power BI workspaces: location is also not available. I have checked other similar client M365 tenants, and both of these locations are available by default. Any insight would be appreciated.
Adaptive Scopes
I'm setting up adaptive scopes in MS Purview for data retention testing, focusing on Entra groups. However, when I create a test adaptive scope using the 365 groups scope and add a query with the group's display name, it doesn't populate. Some scopes are over 7 days old, despite MS stating it can take up to 3 days for queries to sync. Does anyone have a better method for creating adaptive scopes for Entra groups?Microsoft Purview – Data Security Posture Management (DSPM) for AI
Introduction to DSPM for AI In an age where Artificial Intelligence (AI) is rapidly transforming industries, ensuring the security and compliance of AI integrations is paramount. Microsoft Purview Data Security Posture Management (DSPM) for AI helps organizations monitor AI activity, enforce security policies, and prevent unauthorised data exposure. Microsoft Purview Data Security Posture Management (DSPM) for AI addresses three primary areas: Recommendations, Reports, and Data Assessments. DSPM for AI assists in identifying vulnerabilities associated with unprotected data and enables prompt action to enhance data security posture and mitigate risks effectively. Getting Started with DSPM for AI To manage and mitigate AI-related risks, Microsoft Purview provides easy-to-use graphical tools and comprehensive reports. These features allow you to quickly gain insights into AI use within your organization. The one-click policies offered by Microsoft Purview simplify the process of protecting your data and ensuring compliance with regulatory requirements. Prerequisites for Data Security Posture Management for AI To use DSPM for AI from the Microsoft Purview portal or the Microsoft Purview compliance portal, you must have the following prerequisites: You have the right permissions. Monitoring Copilot interactions requires: Users are assigned a license for Microsoft 365 Copilot. o Microsoft Purview auditing enabled. Check instructions for Turn auditing on or off. Required for monitoring interactions with third-party generative AI sites: Devices are onboarded to Microsoft Purview, required for: Gaining visibility into sensitive information that's shared with third-party generative AI sites. (e.g., credit card numbers pasted into ChatGPT). Applying endpoint DLP policies to warn or block users from sharing sensitive information with third-party generative AI sites. (e.g. a user identified as elevated risk in Adaptive Protection is blocked with the option to override when they paste credit card numbers into ChatGPT) The Microsoft Purview browser extension is deployed to users and required to discover site visits to third-party generative AI sites. Things to consider Recommendations may differ based on M365 licenses and features. Not all recommendations are relevant for every tenant and can be dismissed. Any default policies created while Data Security Posture Management for AI was in preview and named Microsoft Purview AI Hub won't be changed. For example, policy names will retain their Microsoft AI Hub -prefix. In this blog post we are going to focus on Recommendations. Recommendations Let's explore each of the recommendations in detail, which will encompass one-click policy creation, data assessments, step-by-step guidance, and regulations. The data in the reports section will be contingent upon the completion of each recommendation. Figure 1: Recommendations – DSPM for AI Control unethical behaviour in AI Type: One-click policy Solution: Communication Compliance Description: This policy identifies sensitive information within prompts and response activities in Microsoft 365 Copilot. Action: Create policy to setup a one-click policy. Conditions: Content matches any of these trainable classifiers: Regulatory Collusion, Stock manipulation, Unauthorized disclosure, Money laundering, Corporate Sabotage, Sexual, Violence, Hate, Self-harm By default, all users and groups are added. The customisation of the policy is also available during the one-click policy creation process. Figure 2: Recommendations – One-click policy Guided assistance to AI regulations Type: New AI regulations Solution: Compliance manager Description: This recommendation is based on the NIST AI RMF regulations, suggesting actions to help users protect data during interactions with AI systems. Action: Monitor AI interaction logs: Go to Audit logs, configure search with workload filter, select copilot and sensitive information type and review search results. Monitor AI interactions in other AI apps: Navigate to DSPM for AI and review interactions in other AI apps for sensitive content and turn on policies to discover data across AI interactions and other AI apps. Flag risky communication and content in AI interactions: Create Communication compliance policy to define the necessary conditions and fields and select Microsoft Copilot as location. Prevent sensitive data from being shared in AI apps: Create Data loss prevention (DLP) policy with sensitive information type as conditions for Teams and Channel messages location. Manage retention and deletion policies for AI interactions: Create a retention policy for Teams chat and Microsoft 365 Copilot interactions to preserve relevant AI activities for a longer duration while promptly deleting non-relevant user actions. Protect sensitive data referenced in Copilot responses Type: Assessment Solution: Data assessments Description: Use data assessments to identify potential oversharing risks, including unlabelled files. Action: Create Data Assessments, Navigate to DSPM for AI - Data Assessments and Create Assessments. Enter assessment name and description Select users and data sources to assets for oversharing data Conduct the assessment scan and review the results to gain insights into oversharing risks and recommended solutions to restrict access to sensitive data. Implement the necessary fixes to protect your data. Discover and govern interactions with ChatGPT Enterprise AI (preview) Type: ChatGPT Enterprise AI (Data discovery) Solution: Microsoft Purview Data Map Description: Register ChatGPT Enterprise workspace to discover and govern interactions with ChatGPT Enterprise AI. Action: If you’re organisation is using ChatGPT Enterprise, then enable the Connector In Microsoft Azure, use Key Vault to manage credentials for third-party connectors: Use Key Vault to create and manage the secret for the ChatGPT Enterprise AI Connector. In Microsoft Purview, configure the new connector using Data Map: How to manage data sources in the Microsoft Purview Data Map Create and start a new scan: Create a new scan, select credential, review, and run the scan. Protect sensitive data referenced in Microsoft 365 Copilot (preview) Type: Data Security Solution: Data loss prevention Description: Content with sensitivity labels will be restricted from Copilot interactions with a data loss prevention policy. Action: Create a custom DLP policy and select Microsoft 365 Copilot as the data source. Create a custom rule o Condition: content contains sensitivity labels. o Action: Prevent Copilot from processing content. Figure 3: Custom DLP policy condition and action Fortify your data security Type: Data security Solution: Data loss prevention Description: Data security risks can range from accidental oversharing of information outside of the organization to data theft with malicious intent. These policies will protect against the data security risks with AI apps. Action: A one-click policy is available to create a data loss prevention (DLP) policy for endpoints (devices), aimed at blocking the transmission of sensitive information to AI sites. It utilises Adaptive Protection to give a warn-with-override alert to users with elevated risk levels who attempt to paste or upload sensitive information to other AI assistants in browsers such as Edge, Chrome, and Firefox. This policy covers all users and groups in your org in test mode. Figure 4: Block with override for elevated risk users Information Protection Policy for Sensitivity Labels Type: Data security Solution: Sensitivity Labels Description: This policy will set up default sensitivity labels to preserve document access rights and protect Microsoft 365 Copilot output. Action: Create policies will navigate to Information protection portal to set up sensitivity labels and publishing policy. Protect your data from potential oversharing risks Type: Data Security Solution: Data Assessment Description: Data assessments provide insights on potential oversharing risks within your organisation for SharePoint Online and OneDrive for Business (roadmap) along with fixes to limit access to sensitive data. This report will include sharing links. Action: This is a default oversharing assessment policy. To see the latest oversharing scan results: Select View latest results and choose a data source. Complete fixes to secure your data. Figure 5: Data assessments – Oversharing assessment data with sharing links report Use Copilot to improve your data security posture (preview) Type: Data security posture management Solution: Data security posture management (DSPM) Description: Data Security Posture Management (preview) combines deep insights with Security Copilot capabilities to help you identify and address security risks in your org. Benefits: Data security recommendations Gain insights into your data security posture and get recommendations protecting sensitive data and closing security gaps. Data security trends Track your org's data security posture over time with reports summarizing sensitive label usage, DLP policy coverage, changes in risky user behaviour, and more. Security Copilot Security Copilot helps you investigate alerts, identify risk patterns, and pinpoint the top data security risks in your org.Set Up Endpoint DLP Evidence Collection on your Azure Blob Storage
Endpoint Data Loss Prevention (Endpoint DLP) is part of the Microsoft Purview Data Loss Prevention (DLP) suite of features you can use to discover and protect sensitive items across Microsoft 365 services. Microsoft Endpoint DLP allows you to detect and protect sensitive content across onboarded Windows 10, Windows 11 and macOS devices. Learn more about all of Microsoft's DLP offerings. Before you start setting up the storage, you should review Get started with collecting files that match data loss prevention policies from devices | Microsoft Learn to understand the licensing, permissions, device onboarding and your requirements. Prerequisites Before you begin, ensure the following prerequisites are met: You have an active Azure subscription. You have the necessary permissions to create and configure resources in Azure. You have setup endpoint Data Loss Prevention policy on your devices Configure the Azure Blob Storage You can follow these steps to create an Azure Blob Storage using the Azure portal. For other methods refer to Create a storage account - Azure Storage | Microsoft Learn Sign in to the Azure Storage Accounts with your account credentials. Click on + Create On the Basics tab, provide the essential information for your storage account. After you complete the Basics tab, you can choose to further customize your new storage account, or you accept the default options and proceed. Learn more about azure storage account properties Once you have provided all the information click on the Networking tab. In network access, select Enable public access from all networks while creating the storage account. Click on Review + create to validate the settings. Once the validation passes, click on Create to create the storage Wait for deployment of the resource to be completed and then click on Go to resource. Once the newly created Blob Storage is opened, on the left panel click on Data Storage -> Containers Click on + Containers. Provide the name and other details and then click on Create Once your container is successfully created, click on it. Assign relevant permissions to the Azure Blob Storage Once the container is created, using Microsoft Entra authorization, you must configure two sets of permissions (role groups) on it: One for the administrators and investigators so they can view and manage evidence One for users who need to upload items to Azure from their devices Best practice is to enforce least privilege for all users, regardless of role. By enforcing least privilege, you ensure that user permissions are limited to only those permissions necessary for their role. We will use portal to create these custom roles. Learn more about custom roles in Azure RBAC Open the container and in the left panel click on Access Control (IAM) Click on the Roles tab. It will open a list of all available roles. Open context menu of Owner role using ellipsis button (…) and click on Clone. Now you can create a custom role. Click on Start from scratch. We have to create two new custom roles. Based on the role you are creating enter basic details like name and description and then click on JSON tab. JSON tab gives you the details of the custom role including the permissions added to that role. For owner role JSON looks like this: Now edit these permissions and replace them with permissions required based on the role: Investigator Role: Copy the permissions available at Permissions on Azure blob for administrators and investigators and paste it in the JSON section. User Role: Copy the permissions available at Permissions on Azure blob for usersand paste it in the JSON section. Once you have created these two new roles, we will assign these roles to relevant users. Click on Role Assignments tab, then on Add + and on Add role assignment. Search for the role and click on it. Then click on Members tab Click on + Select Members. Add the users or user groups you want to add for that role and click on Select Investigator role – Assign this role to users who are administrators and investigators so they can view and manage evidence User role – Assign this role to users who will be under the scope of the DLP policy and from whose devices items will be uploaded to the storage Once you have added the users click on Review+Assign to save the changes. Now we can add this storage to DLP policy. For more information on configuring the Azure Blob Storage access, refer to these articles: How to authorize access to blob data in the Azure portal Assign share-level permissions. Configure storage in your DLP policy Once you have configured the required permissions on the Azure Blob Storage, we will add the storage to DLP endpoint settings. Learn more about configuring DLP policy Open the storage you want to use. In left panel click on Data Storage -> Containers. Then select the container you want to add to DLP settings. Click on the Context Menu (… button) and then Container Properties. Copy the URL Open the Data Loss Prevention Settings. Click on Endpoint Settings and then on Setup evidence collection for file activities on devices. Select Customer Managed Storage option and then click on Add Storage Give the storage name and copy the container URL we copied. Then click on Save. Storage will be added to the list. Storage will be added to the list for use in the policy configuration. You can add up to 10 URLs Now open the DLP endpoint policy configuration for which you want to collect the evidence. Configure your policy using these settings: Make sure that Devices is selected in the location. In Incident reports, toggle Send an alert to admins when a rule match occurs to On. In Incident reports, select Collect original file as evidence for all selected file activities on Endpoint. Select the storage account you want to collect the evidence in for that rule using the dropdown menu. The dropdown menu shows the list of storages configured in the endpoint DLP settings. Select the activities for which you want to copy matched items to Azure storage Save the changes Please reach out to the support team if you face any issues. We hope this guide is helpful and we look forward to your feedback. Thank you, Microsoft Purview Data Loss Prevention Team
