Set MS SQL Server authentication mode

In SQL Server Management Studio Express, right-click the root element in Object Explorer.

Then select Properties.

properties menu

In the Server Properties window, click the Security option and select SQL Server and Windows Authentication mode. Then click the OK button.

allow sql server and windows authentication mode

If you are finished, you have to restart the SQL Server. Right-click the root element in Object Explorer. Finally, select Restart.

restart the server

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