How to Set Up Microsoft Defender for Business

What is Microsoft Defender for Business?

Microsoft Defender for Business provides enterprise-grade endpoint security for businesses with up to 300 users. It protects Windows, macOS, iOS, and Android devices from viruses, ransomware, phishing, and advanced threats.

Step 1 — Access the Microsoft 365 Defender Portal

Go to security.microsoft.com and sign in with your Global Administrator account. This is where you manage all endpoint security settings.

Step 2 — Run the Setup Wizard

The first time you open the Defender portal, a setup wizard will guide you through configuring security policies, onboarding devices, and setting up email notifications. Follow each step — it takes about 10 minutes.

Step 3 — Onboard Devices

Go to Assets → Devices → Onboard devices. Choose your deployment method — for Windows devices, the simplest is using a local script or Microsoft Intune if you have it. Run the script on each device to enroll it.

Step 4 — Review Security Recommendations

After onboarding, go to Vulnerability management → Recommendations. Defender will show you a prioritised list of security improvements for your devices — apply them to strengthen your security posture.

Step 5 — Set Up Alerts

Go to Settings → Email notifications to configure alerts for threat detections, new vulnerabilities, and device health issues. Set these to notify your IT administrator immediately.