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Microsoft 365 Security · Resource

Defender Deployment Guide

A phased deployment guide for rolling out Defender for Office 365 and Defender for Endpoint across a tenant.

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Defender Deployment Guide

A phased deployment guide for rolling out Defender for Office 365 and Defender for Endpoint across a tenant.

Phase 1 — Baseline Enablement

  • Enable Safe Links and Safe Attachments tenant-wide (Defender for Office 365).
  • Deploy Defender for Endpoint next-gen antivirus and attack surface reduction rules in audit mode.

Phase 2 — Detection & Response

  • Enable EDR (Plan 2) and review the first two weeks of alerts before tuning.
  • Move ASR rules from audit to block mode for confirmed-safe rules.

Phase 3 — Correlation

  • Confirm Defender XDR is correlating signal across Office 365, Endpoint, and Entra ID Protection.
  • Establish a routine for reviewing correlated incidents.

Related Resources

  • Microsoft Defender for Endpoint — /knowledge-center/cloud-productivity/microsoft-365-security/microsoft-defender-for-endpoint

This document is a starting-point resource, not legal or compliance advice. Review it against your organization's actual systems before adoption — see the full Microsoft 365 Security & Entra ID Hub for the reasoning behind each recommendation, or browse the full Resource Library.

Microsoft 365 Security & Entra ID

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