Microsoft Purview Data Loss Prevention Setup

Most data leaks aren't hacks. They're an email sent to the wrong person, a spreadsheet of Social Security numbers shared with "anyone with the link," or a file of patient records attached to a message headed outside the company. Microsoft Purview data loss prevention (DLP) watches for sensitive information in Microsoft 365 and steps in before it leaves. We design the policies, roll them out carefully, and tune them so they protect data without getting in the way of work.

What the project includes

• Sensitive data discovery. Finding out what sensitive information you have and where it lives across Exchange, SharePoint, OneDrive and Teams.
• Policy design. DLP policies built around your industry and the data you actually handle: patient health information for medical practices, account and Social Security numbers for financial firms, card numbers for businesses that take payments. Microsoft's built-in templates for common U.S. regulations are the starting point, adjusted to fit how you work.
• Test mode first. New policies run in simulation, so we can see what they would catch before anything is blocked.
• User guidance. Policy tips that explain to staff why a message or file was flagged and what to do instead, rather than silent blocks that generate help desk calls.
• Sensitivity labels. Where it fits, labels that mark documents as confidential and carry protection with them.
• Alerts and reporting. Alerts routed to the right people and reports that show what the policies are catching.
• Copilot and AI. If you use Microsoft Copilot (formerly Microsoft 365 Copilot), Purview can also keep sensitive content out of AI responses. Our AI data security project covers the wider AI risk.

Licensing, in plain terms

DLP for Exchange email, SharePoint and OneDrive is included in Microsoft 365 Business Premium, E3 and E5. DLP for Teams chat messages and some advanced features need E5 or Microsoft's Purview add-ons. We review your licenses before we design anything, so you know exactly what's possible with what you already pay for. (Microsoft's Purview service description has the details.)

Who it's for

Organizations that handle regulated or confidential data in Microsoft 365: healthcare practices protecting patient information under HIPAA, financial firms, law firms and anyone whose clients or insurer ask how sensitive data is protected. It's a natural next step after a Google Workspace to Microsoft 365 migration, and it supports the documentation side of compliance consulting.

How the work runs

1. Discovery. We review your licenses, data types and where sensitive information is stored and shared.
2. Policy plan. You approve which data is protected, where, and what happens when a policy is triggered.
3. Simulation. Policies run in test mode while we review matches and tune out false alarms.
4. Staged rollout. Policy tips first, then blocking where it's warranted, rolled out to groups of users.
5. Handover. You get the policy documentation, alert routing and a walkthrough of the reports.

The timeline depends on how many policies you need and how long the simulation needs to run to get the tuning right.

What you get at the end

• DLP policies protecting the sensitive data you identified.
• Staff who see a clear explanation when something is flagged.
• Alerts going to the right people.
• Documentation you can show an auditor, insurer or client.

Keeping it tuned

DLP policies need attention as your data and staff change. Our cloud services team reviews alerts, adjusts policies and keeps Purview in step with your Microsoft 365 environment. Mash IT is based in Lexington, Kentucky, and supports Microsoft 365 for businesses across Central Kentucky.