The Top 3 Ways to Restrict Microsoft 365 Copilot for Safer, Smarter AI
- Ryan Bowler
- Jul 3
- 3 min read
Microsoft 365 Copilot is a powerful AI tool, which acts like an expert researcher with access to your organization's digital library. It retrieves information from emails, files, and SharePoint Online to answer questions and streamline work. But like any good library, you need a system to designate which sections are open for public research and which are restricted.
Because Copilot adheres to permissions, it will never show a user data they don't already have permission to see. While this is a great starting point, effective information governance goes a step further. It requires deciding which SharePoint sites, even if permissions are correct, should be excluded from AI processing altogether. This isn't about limiting Copilot; it's about guiding it. By strategically blocking certain sites, you ensure Copilot reads from the most relevant, accurate, and appropriate information, making it a more effective and safer tool for everyone.
What’s the context for blocking a site?
While the decision to exclude a SharePoint site may stem from issues like rogue or faulty permissions, the context of the data within the site is also an important factor. Some common examples of sites that are strong candidates for being blocked include:
Executive Sites: unannounced strategic plans or sensitive leadership discussions. Even though executives have access, this type of information shouldn’t be provided to most general users in Copilot queries.
HR Sites: performance reviews, salary data, or internal employee investigations. This information is highly sensitive, making it crucial to limit access.
Legacy Content: outdated project files or old policies. Allowing Copilot to access these sites could pollute its knowledge base, potentially leading to answers based on obsolete information.
Research & Development: Brainstorming sites where ideas are still under development and haven’t yet been implemented.
What’s available in your toolbox?
Fortunately, there are a few tools at your disposal to create these digital walls. Depending on the situation, there a few different locks to explore:
Restrict Content Discovery: Microsoft provides specific control within SharePoint site settings called "Restrict content from Microsoft 365 Copilot." This is the ideal tool for the job. It’s a simple toggle switch that blocks Copilot from processing the site's content. The biggest advantage is that it does not affect user search. Your team can still find what they need with only the AI being restricted.
The Search Index: The classic method for making a site invisible is to remove it from the Microsoft Search Index. By disabling search in the site settings, you effectively hide the entire site from everyone, including Copilot. The caveat is that no one is able to find the content on this site via search anymore. This method is great for old archives or dusty sites that you intentionally want to make difficult to access.
Sensitivity Labels: This approach aligns perfectly with best practices for data governance. Instead of locking the whole site, you can lock individual files. By applying a sensitivity label that secures a document, you ensure only users with explicit rights can open it. Since Copilot operates under the user's permissions, it also cannot access the content of that secure file.
Is there a strategy?
A successful strategy for managing Copilot access begins with a strong foundation of permissions. Once that security model is sound, you can apply the right tool for the job, using tools such as direct site restriction, site search blocking for specific cases, and sensitivity labels for granular, file-level control. The approach should be documented to create a clear record of why certain sites are excluded and communicated clearly to users to manage expectations, especially when search functionality could be affected. Ultimately, the strategy is not about limiting Copilot’s potential. It's about tweaking its knowledge base for data security and efficiency.
