Error "Login failed for user" When Refreshing Extract or Opening View Based on Live Connection to SQL Server

Issue

When opening views with live data source connections, you may see the following error:

"Session Ended by Server
An unexpected error occurred. If you continue to receive this error please contact your Tableau Server Administrator.
Session ID: <string>
[Microsoft][SQL Server Native Client 11.0][SQLServer]Login failed for user <username>.
Integrated authentication failed.
create.xml
class DataSourceException
Unable to connect to the server <server name>. Check that the server is running and that you have access privileges to the requested database.
<Timestamp>
Would you like to reset the view?"

Or when working with extracts on Tableau Server, you may notice that workbooks that are connected to Microsoft SQL Server data sources do not refresh or you see the following error message in the Background Tasks admin view:

SQL Server database error 0x80040E4D: Login failed for user <username>

Note: <username> in the error is different from the user who published workbook.

Environment

Tableau Server
Windows NT authentication
Microsoft SQL Server data source

Resolution

Option 1:

Allow the Tableau Server Run As User account permissions to access the SQL Server database.

Option 2:

Edit the SQL Server connection and specify the credentials manually using Tableau Desktop.
During publish, choose to embed the database credentials.
Note: This method requires the SQL Server to be configured for mixed-mode authentication. For more information, see Change Server Authentication Mode at Microsoft docs.

Option 3:

Configure Tableau Server and SQL Server to use impersonation as described at SQL Server Impersonation.

Cause

When using Windows NT authentication, it is not possible to embed database credentials because Tableau Desktop does not receive the actual username or password of the person who publishes the workbook. Instead, Windows provides a temporary authentication token that cannot be saved by Tableau Server.