You have Office365 account and you getting error connecting to CRM Online from BIDS to write your custom FetchXML report:
An authentication error occurred while connecting to server
Make sure that the connection string and credentials are correct, and try again.
1) It is not very obvious – but you will need to install “Microsoft Online Services Sign-In Assistant for IT Professionals RTW” to route correctly your requests to Discovery server designated for Office365 users
2) Then in the Connection string of your FetchXML data source – you will have to type the following
(this Discovery server address is for North American Office365 accounts)
3) your_unique_orgname – is located in CRM: under Settings –> Customizations –> Developer Tools
Hope this will save your time
This solution was found thanks to Peter Moss’ article
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