If you are an existing Microsoft Defender for Endpoint customer but have Exchange servers that are not onboarded, see instructions at this documentation site for onboarding Windows Server to Microsoft Defender for Endpoint.
- DOCS: Onboard Windows servers to the Microsoft Defender for Endpoint service
https://docs.microsoft.com/en-us/microsoft-365/security/defender-endpoint/configure-server-endpoints?view=o365-worldwide
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