Imagine standing on a runway next to a brand-new supersonic jet. It’s shiny, powerful, and can almost fly itself. That jet is Microsoft 365 Copilot. It can help your team work faster, think creatively, and get things done in record time.

But no pilot would jump into a super-fast jet without checking the fuel, the cargo, or the crew. A tiny loose bolt at 30,000 feet can cause a disaster.

Deploying Copilot works the same way.
Copilot connects to everything: emails, chats, files, meetings, and more. It uses something called a “Semantic Index,” which is like a smart map of all your data. But Copilot is also a mirror. If your data is messy, Copilot becomes messy. If your permissions are too open, Copilot will follow those open doors. If old “ghost accounts” still exist, Copilot may even let them fly the plane.

This is where Copilot data governance becomes your most important tool.
This guide gives CISOs a clear, plain-English, 10-step checklist to prepare your environment before you press “On.”

Phase 1: Check the Passengers (Identity & Access)

Step 1: Clean Up Entra ID (The ID Check)

Think of Entra ID as the boarding gate. If your passenger list is full of ghosts or strangers, the whole flight is unsafe.

Over the years, companies collect “identity debt”:

• Old employees whose accounts were never deleted
• Guest users from old projects
• Test accounts like “Admin_Test1”
• Service accounts mixed with human accounts

Why ghost accounts are dangerous:

• Licensing waste: You might pay for Copilot seats for people who no longer exist.
• Security holes: Hackers love forgotten accounts because nobody watches them. A hacker could log in and ask Copilot, “Summarize the CEO’s merger emails,” and Copilot would follow the permissions.

Turn on MFA

Passwords are like house keys. Easy to lose, easy to copy.
MFA is like a fingerprint scanner. Even if someone knows your password, they can’t get in.

If users get “MFA fatigue,” turn on number matching so they must type the number shown on the screen into their phone. This proves the person is actually present.

Step 2: Secure Devices with Intune (The Cockpit Check) - Copilot data governance

If users are the pilots, then devices are the planes. You don’t want rusty planes in the air.

The Rusty Plane Example

Imagine an employee, let's call him Dave. Dave likes to use his personal tablet for work. He has Copilot on it. But Dave also lets his kids play games on that tablet. He doesn't have a passcode on it. He hasn't updated the software in two years.

If Dave downloads a malicious game, or if he leaves his tablet in a taxi, that device is compromised. A thief could open Copilot and ask, "Show me Dave's recent confidential files." Because the device is untrusted, your data is exposed.

How Intune protects your fleet

You need a traffic controller for your devices. This is Microsoft Intune. It allows you to set rules for any device that wants to access your data

• Health checks: Block devices without updates or antivirus.
• Encryption: Use BitLocker or FileVault so stolen data can't be read.
• App protection: If Dave refuses to enroll his personal phone, use app-only protection so work data stays inside Outlook and Teams. You can wipe work data without touching personal photos.

The Ripple Effect: By securing the devices, you create a "Chain of Trust." You trust the user (Entra ID), and you trust the vehicle (Intune). Now, Copilot can operate safely because the environment is clean for Copilot data governance.

Phase 2: Secure the Cargo Hold (Your Data)

This is where most problems hide. Copilot uses the Semantic Index to understand your files, not just search them. It can connect concepts you didn’t know were related.

This makes it very helpful and very risky.

Step 3: Fix Permissions (Just Enough Access)

Many companies practice “Security by Obscurity.” They bury a sensitive file deep inside folders and assume nobody will find it.

Copilot will find it.

The Copilot Flashlight

If a user asks, “What is the budget for the secret project?” Copilot shines a bright flashlight through every file that user can access. If the file is open even by mistake, Copilot will read it and summarize it.

The “Everyone” Trap

The group “Everyone except external users” is one of the most dangerous defaults.
People use it to share lunch menus… and later accidentally use it to share HR folders or financial drafts.

Fixing permissions

• Scan site “Members” groups and remove “Everyone.”
• Create role-based groups (HR Team, Finance Team).
• Hunt for broken inheritance - when one file in a secure folder has wider access than the folder itself. It’s like locking the door but leaving a window open.

Partners like Communication Square can scan millions of files to spot these issues quickly.

Step 4: Clean Up Sharing Links (Runway Debris)

“Anyone with the link” = anonymous access.
Copilot treats these links as open access because technically, they are.

Why these links are dangerous

• They don’t require login—your logs only show “Anonymous User.”
• They last forever unless you set an expiration date.

A link emailed five years ago might still open a sensitive file today.

Fix the debris

• Turn off “Anyone” links.
• Require login for all internal and external sharing.
• Set expiration dates on links used for public materials.
• Use “Organization” links only when needed.

Step 5: Reduce ROT (Redundant, Obsolete, Trivial Data)

A plane can’t take off if it's too heavy.
Your data estate can’t support Copilot well if ROT weighs it down.

Zombie Data Example

Imagine you have a travel policy from 2015 that allows First Class tickets. You updated it in 2020 to say Economy only. But the old file still exists.

If someone asks Copilot about the travel policy, it may grab the old one and give the wrong answer.

Copilot assumes your data is true even if it’s outdated.

Fixing ROT

Use Microsoft Purview to:

• Auto-delete old data
• Keep what’s needed for legal holds
• Remove trivial files

Important note

Copilot conversations are also stored in a hidden place called SubstrateHolds in each mailbox. Decide how long to keep them based on your compliance rules.

Phase 3: Set the Navigation System (Protection & Governance)

Now that your data is clean, you need rules that tell Copilot where it can go and where it cannot.

Step 6: Use Sensitivity Labels (Digital Luggage Tags)

When you check a bag at the airport, it gets a tag. Files need tags too.

Labels include:

• Public
• General
• Confidential
• Highly Confidential

Why Copilot needs labels

If a file is labeled Highly Confidential and encrypted, Copilot must check permissions before touching it.

If a user doesn’t have the key, Copilot acts like the file doesn’t exist.

Good labeling strategy

• Follow the 5x5 rule: no more than 5 labels and 5 sublabels.
• Use container labels to auto-label new files in a Team or SharePoint site.
• Use auto-labeling for credit cards, Social Security numbers, or secret keywords.

Step 7: Add Data Loss Prevention (The Autopilot Limits)

DLP is your guardrail system. It prevents people from accidentally sending confidential data outside your organization.

Two ways DLP protects you

Policy Tips: A gentle warning.
“Hey, this file has credit card numbers. Are you sure you want to send it?”

Hard Blocks:
Stops the email or sharing action completely.

DLP with Copilot

You can tell DLP to block Copilot from using content that breaks rules.
This creates No-Fly Zones for sensitive files.

Step 8: Turn On Auditing & eDiscovery (The Black Box)

Every plane has a flight recorder. Your Copilot environment needs one too.

Logs help you see:

• Who used Copilot
• What files were accessed
• What prompts were used
• When activities happened

Legal and compliance teams must also learn how to search Copilot prompts and answers during investigations.

Phase 4: Prepare the Crew (People & Process)

Step 9: Train Your Team (Flight School)

Copilot is powerful, but users need to learn how to “talk” to it.

Bad Prompt

“Write an email.”

Good Prompt

“Act as a project manager. Write a short email explaining the two-week delay because of supply chain issues. Suggest a new delivery date of November 1. Keep the tone apologetic but professional.”

Build a Champions Network

• Choose 1–2 excited users in each department.
• Train them deeply.
• Let them help others in their own team.
• Meet with them for feedback—these users spot real-world issues fast.

Step 10: Roll Out in Phases (Pilot Program)

Never launch Copilot to everyone at once.

Safer rollout plan

1. IT and Compliance
2. Champions
3. Early adopters (one department at a time)
4. Full organization

Create a Break-Glass Procedure

You need a fast emergency plan for:

• Strange Copilot behavior
• Unexpected data exposure
• Security incidents or zero-day attacks

Make sure you can disable Copilot quickly for certain users or for the whole company, while you investigate.

Conclusion: You’re Cleared for Takeoff

By following these 10 steps, your Copilot environment becomes safe, clean, and ready for flight:

• Ghost accounts removed
• Devices secured
• Permissions tightened
• Risky links closed
• ROT deleted
• Labels applied
• DLP rules active
• Auditing enabled
• Users trained
• Rollout structured

Strong Copilot data governance doesn’t just protect you, it boosts trust and productivity across your whole organization.

Copilot isn’t just another tool. It’s an upgrade to your entire data culture. And if this checklist feels heavy, partners like Communication Square help organizations scan permissions, configure DLP, and prepare for a safe, smooth Copilot deployment.

Ready to get started? Schedule a meeting with our team today. Let’s ensure your flight to the future is smooth, secure, and supersonic.