I'm attempting to access data from an HTTPS REST API for import into Power Pivot. The API in question just passes the username and password as URL parameters, rather than OAuth or setting header values.
Accessing the URL directly in a web browser works perfectly (response data is pipe-delimited text), but through Power Pivot (and Power Query) I get a "400: Bad Request".
URL format is like the below (obfuscated):
I've tried playing with the Advanced Settings in Power Pivot to no avail, and have also tried setting up a Data Feed within SharePoint, but all this does is wrap the URL (above) in an .atomsvc document and I end up with the same error.
Any suggestions where to start in order to allow Power Pivot to query this URL?