Archived PowerShell 0.1 script that sends an Exchange Autodiscover GetFederationInformation request for an input domain, uses returned federated domains (not necessarily every accepted domain) to derive an onmicrosoft.com tenant prefix, and probes two legacy tenant-derived atp.azure.com URL forms. Treat the MDI result as an unverified heuristic: HTTP 200 produces a 'looks like' message, while request exceptions are reported as 'no instance'; neither confirms deployment. Current Microsoft documentation directs admins to authenticated Defender portal settings for workspace and sensor status and documents a workspace-specific sensor API endpoint.
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