By default, the Encrypt connection check box is selected to signify that Power BI Desktop connects to your database using an encrypted connection. If a connection to your SQL Server is not established using an encrypted connection, that Power BI Desktop prompts you to connect using an unencrypted connection. Once you click OK, you'll be directly prompted to turn off encryption. Or you can go to File->Options and Settings -> Data Source Settings, choose your SQL Server data source and select Edit and uncheck "Encrypt Connections" option.
In addition, when you connect to SQL Server in Power BI Desktop, you need to select the authentication mode to connect to the SQL Server database.
a. Windows: This is the default selection. Select this if you want to connect using Windows authentication.
b. Database: Select this if you want to connect using SQL Server authentication. After you select this, specify a user name and password to connect to your SQL Server instance.
Community Support Team _ Lydia Zhang
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