By default, some SQL Server installations do not have TCP/IP enabled for remote access. This is required for use by a remote SharePoint server. To enable TCP/IP, simply open SQL Server Configuration Manager (Start, All Programs, Microsoft SQL Server 2008 R2 – Configuration Tools, SQL Server Configuration Manager) and navigate to SQL Server Network Configuration, Protocols for <INSTANCENAME>. Change the TCP/IP to Enabled, as shown in Figure 3.6. If this is not done, SharePoint cannot connect to the SQL Server.
Figure 3.6. Enabling TCP/IP support in SQL Configuration Manager.