Since March 2018 release of PBI Report Server, testing connections of OData data sources with Baisc Authentication fails with "Log on failed. Ensure the user name and password are correct." Scheduled refresh of reports based on those data sources fails as well, with error 500 returned from the source. No useful error message is logged in the PBI RS log files. It appears that PBI RS is sending wrong credentials. PBI Desktop works fine. A similar issue has been reported for PBI Service more than a year ago:
Has anyone experienced this issue?
I'm encountering this same issue with the March 2018 release. Did you ever find a resolution? I'm attempting to connect with OData to MS Project server. I get the exact same error mentioned when I attempt to test the connection.
Testing Connection on ODATA is buggy, most likely if HTTP is involved (as opposed to pure HTTPS). Scheduled Refresh issues was an issue with the provider, a mere coincidence with March release.