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If allowing the SQL Server program through the firewall as per above does not solve the connectivity issue, then we must check that the SQL Server itself is listening for TCP/IP connections. To do this the "SQL Server Configuration Manager" is used on the SQL Server machine.
1. Launch the "SQL Server Configuration Manager". In Windows Server 2012 R2 this is done by clicking on the Start menu, typeing "SQL Server Con", and then clicking the "SQL Server 2014 Configuration Manager" icon which appears on the right.
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