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Microsoft Defender for Office 365

Also known as MDO

Microsoft's email and collaboration security layer, protecting against phishing, malicious links, and weaponized attachments.

Plan 1 provides Safe Links and Safe Attachments, checking destinations at the moment of click and detonating files before delivery. Plan 2 adds attack simulation training, automated investigation and response, and threat tracking.

Plan 1 is now included in E3 and Business Premium. Plan 2 comes with E5 or the Defender Suite.

Where this comes up

Microsoft Defender for Office 365 sits inside our microsoft 365 and cloud work. If you are trying to work out what this means for your own environment rather than in the abstract, that is the page worth reading next, and a short call will get you a straight answer faster than either.

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Related terms

Email security The layer that inspects inbound and outbound mail for phishing, malware, impersonation, and data leakage. Phishing A fraudulent message designed to trick someone into handing over credentials, approving a login, or opening something malicious. Sandboxing Opening a suspicious file in an isolated environment to watch what it does before letting it near a real system. Microsoft Defender Suite Microsoft's bundled security add-on: Entra ID P2, Defender for Endpoint P2, Defender for Office P2, Defender for Identity, and Defender for Cloud Apps.

More in microsoft 365 and cloud

300-seat capBYODCloud migrationCloud Solution ProviderData loss preventioneDiscoveryExchange OnlineInfrastructure as a service

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