Login failed for user in Windows Authentication mode

When connecting to SQL Server using Windows Authentication mode in Bold BI, it will throw the following error.

Why this issue occurred

NT AUTHORITY/SYSTEM is not added to IIS/IIS EXPRESS for accessing SQL Server in Windows Authentication mode.

The steps for adding NT AUTHORITY/SYSTEM to access SQL Server Windows Authentication mode in IIS or IIS EXPRESS

In Microsoft SQL Server Management Studio, please perform the following actions on the server.

1. Right click on “Login” and select New Login to add respective login into SQL Server.
   

2. Click on the “Search” button, then select Advanced -> Find Now -> SYSTEM in the newly opened window.
   

   

3. Then click “OK” to add the login NT AUTHORITY/SYSTEM. Once it has been added, we will be able to access Windows authentication mode in Bold BI.