Click on the following link to bring you to the site where you can download SQL Server 2017 Express, as shown in Figure 16.1.1:
https://www.microsoft.com/en-us/sql-server/sql-server-editions-express
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Figure 16.1.1: Download screen for SQL Server 2017 Express edition
Next, click on the Download now button. When the download is complete, double-click on SQL Server2017-SSEI-Expr.exe. Answer Yes on the User Account Control screen.