After upgrading Tableau Server and/or attempting to load a view on Tableau Server the following error might occur:When some users try to access a view on Tableau Server, they receive an error saying:
HTTP 400: There was an error with the data source "<data source name>". Verify that the data source is configured correctly.
Additionally, when loading a view in Tableau Server, an extra error message might appear indicating that the session was ended by server. and will contain an HTTP 400 error along with the following error:
"Unable to connect to the server 'localhost'".