Microsoft 365 Copilot security settings
Microsoft 365 Copilot Security Settings: Top 10
Copilot comes as a personal app, Microsoft 365 Copilot in your company's tenant, Copilot Studio for building agents and Azure OpenAI for building apps. Microsoft 365 Copilot answers from everything a person can already open, so its settings start with who can see what. These are the 10 settings that matter most, where to find each one and what good looks like.
In short: start with (1) SharePoint and OneDrive external sharing and default link type, (2) DSPM oversharing assessment and (3) Restricted Content Discovery, then work down the list below.
By Jon Rose, Founder & Managing Partner, IOmergent. Vendor facts as of October 2026. Not sure which version you have? See which AI account is which.
The top 10 Microsoft 365 Copilot security settings
Most important first. Our free AI Hardening Check walks you through these and the other 40, with direct links, inside your own AI assistant.
-
1SharePoint and OneDrive external sharing and default link type
- Where to find it
- SharePoint admin center > Policies > Sharing: External sharing level for SharePoint and OneDrive (Anyone, New and existing guests, Existing guests, Only people in your organization); File and folder links default; More external sharing settings
- Good looks like
- Default link 'Specific people' or 'Only people in your organization'; external sharing at Existing guests or tighter, no Anyone links (or expiring, view only); guest access expiry set
- Why it matters
- Broad links widen what Copilot and connected AI apps can surface to each user
-
2DSPM oversharing assessment (licensed Copilot)
- Where to find it
- Purview > Solutions > DSPM > Discover > Data risk assessments (older tenants: DSPM for AI (classic)). The default assessment runs weekly on the top 100 sites
- Good looks like
- Weekly assessment reviewed and overshared sites fixed
- Why it matters
- Finds overshared content before Copilot surfaces it
-
3Restricted Content Discovery (licensed Copilot)
- Where to find it
- SharePoint admin center > Sites > Active sites > (site) > Settings > 'Restrict content from Microsoft Copilot'
- Good looks like
- On for sensitive or overshared sites (HR, Finance) while permissions are fixed (needs a Copilot license and SharePoint Advanced Management)
- Why it matters
- Keeps those sites out of Copilot answers and org-wide search, and hides Copilot buttons on the site
-
4DLP for Copilot (Copilot Chat)
- Where to find it
- Purview > Data loss prevention > Policies > Create policy > Custom > Custom policy > location 'Microsoft 365 Copilot and Copilot Chat'. Files uploaded into a prompt are not scanned; changes take up to 4 hours
- Good looks like
- Labeled items blocked; sensitive info types blocked in prompts and from web search; external email excluded (preview)
- Why it matters
- Copilot can cite the file but won't read it
-
5Entra ID user consent settings
- Where to find it
- Microsoft Entra admin center > Entra ID (older docs: Identity > Applications) > Enterprise apps > Consent and permissions > User consent settings > User consent for applications. Default lets users consent to any permission that does not need admin consent
- Good looks like
- User consent disabled, or at most 'Allow user consent for apps from verified publishers, for selected permissions' with only low-impact permissions classified. Changing it does not revoke existing grants
- Why it matters
- Stops users granting AI apps access to their mail and files on their own
-
6Agent and plugin access, user access and sharing
- Where to find it
- Microsoft 365 admin center > Agents > Settings: Agent and plugin access (access types), User access (default All users), Sharing (Agent Builder agents only; Copilot Studio sharing is MCS-4)
- Good looks like
- External publishers off; user access and sharing limited to named groups (Copilot Chat and licensed Copilot)
- Why it matters
- Stops unvetted third-party agents and MCP servers reaching tenant data (user access defaults to all users)
-
7Block personal Microsoft accounts (needs Entra ID P1)
- Where to find it
- Entra admin center > Entra ID > External Identities > Cross-tenant access settings > Default settings > Tenant restrictions; Organizational settings > Add organization 9188040d-6c67 to 4c5b-b112 to 36a304b66dad
- Good looks like
- Blocked, and enforced through Global Secure Access, Windows policy or a proxy header (needs Entra ID P1); do not block copilot.cloud.microsoft
- Why it matters
- Keeps work data out of Microsoft Copilot on a personal Microsoft account
-
8Conditional Access for Copilot (needs Entra ID P1)
- Where to find it
- Entra admin center > Conditional Access > policy targeting 'Enterprise Copilot Platform' (create its service principal first). From a search snippet, not a full doc read
- Good looks like
- Phishing-resistant MFA and a compliant device required
- Why it matters
- Copilot can reach all data the user can open
-
9Copilot audit logging (Copilot Chat)
- Where to find it
- Microsoft Purview portal > Audit, filter on CopilotInteraction (on with Audit Standard). AISystemPlugin.Id = BingWebSearch marks web use. Audit of non-Microsoft AI apps is pay-as-you-go (180 days)
- Good looks like
- Audit on and CopilotInteraction events exported and reviewed
- Why it matters
- Shows who asked what and which files and labels Copilot touched
-
10Retention policy for Copilot interactions (Copilot Chat)
- Where to find it
- Purview > Data lifecycle management > retention policy on the 'Microsoft Copilot experiences' location
- Good looks like
- A deliberate retain or delete period; old 'Teams chats and Copilot interactions' policies split
- Why it matters
- With no policy, prompts and responses are kept until the user deletes them
Microsoft 365 Copilot security settings: common questions
- What are the most important Microsoft 365 Copilot security settings?
- Start with (1) SharePoint and OneDrive external sharing and default link type, (2) DSPM oversharing assessment and (3) Restricted Content Discovery. All 10 are listed on this page, most important first, with where to find each one and what good looks like.
- Does Microsoft 365 Copilot train on our data?
- No. Microsoft doesn't use your prompts, responses or Microsoft Graph data to train its foundation models.
- How long does Microsoft 365 Copilot keep chats?
- You decide, with Microsoft Purview retention policies for Copilot interactions.
- How do people sign in to Microsoft 365 Copilot?
- With your Microsoft Entra ID accounts. Turn on MFA and Conditional Access for Copilot.
- How can I check all the Microsoft 365 Copilot settings quickly?
- Add the free IOmergent AI Hardening Check to your AI assistant and ask: "Run the IOmergent AI Hardening Check for our Microsoft 365 Copilot tenant." It walks you through these and the other 40, with direct links, and nothing leaves your machine without your OK.
Want an expert review?
A self-check can't see which AI apps hold OAuth access to your email, files and code, or confirm the settings match what was reported. Our AI Security Assessment does both, with read-only connections and a live review.
See the AI Security Assessment