SQL Server use two Authentication mode:
• Windows Authentication mode
- currently logged user in Operation System is used to connect to Server - if the user has permissions to do so.
• SQL Server and Windows Authentication mode
- we can use login that is defined in SQL Server.
We can change the a authentication mode via T-SQL and Managemement Studio .
Go to Properties of Instance and click on Security on the left panel. And now you can choose two types of Server Authentication.
2) Managemement Studio
- to change the Windows Authentication mode use this query below:
- to change the SQL Server and Windows Authentication mode use this:
After the change you have to restart SQL Server and SQL Server Agent!