While trying to connect I get the following error: Access to the resource is forbidden

Some of users describe getting the Access to the resource is forbidden error message when connecting to Microsoft Power BI with data sources.

Reason: Incorrect credentials. During the initial connection, incorrect credentials were provided and saved for the data source.

Solution:

At the top-left corner of Power BI Desktop, select the File tab.
Select Options, and then select Settings.
Select Data Source Settings.
Select the data source the “Access to the resource is forbidden” error arises for.
From the drop-down menu, select the Clear Permissions option.
Select the Close button.

Afterward, you can re-enter the correct credentials when connecting the data source using Basic authentication.

If you connect data sources from different instances, ensure to select the full connector URL during the authentication process.