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From the Windows desktop, click Start ► All Programs ► Microsoft SQL Server ► Configuration Tools ► SQL Server Configuration Manager.
The SQL Server Configuration Manager appears.In the console pane, expand SQL Server Services.
In the details pane, right-click the named instance of SQL Server, then click Start.
For example: , SQL Server (MSSQLSERVER)Click OK to close the SQL Server Configuration Manager.
A green arrow on the icon next to the server name and on the toolbar indicates that the server started successfully.