Though connecting to Dynamics 365 from Power BI Desktop is same old process , the As-Is Dynamics 365 9.0 Web API Url would not let you connect. A small change to the D365 API Url needs to be done when attempting a connection from Power BI. The 9.0 in the endpoint Url needs to be replaced with 8.1
Original API :- https://organizationname.api.crm.dynamics.com/api/data/v9.0/
Url to be used :- https://organizationname.api.crm.dynamics.com/api/data/v8.1/
This would help you to prevent the error
Unable to connect We encountered an error while trying to connect. Details:"Odata: The feed's metadata document appears to be invalid."
The same is applicable when connecting using Power Query , Excel etc.
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Note: This approach has been tested on Power BI Desktop version -2.54.4970.961 64-bit (January 2018) and Dynamics 365 Version -1612 (9.0.1.510) (DB 9.0.1.510) online.
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