Setup is unable to connect to SQL server error while installing SCCM 2012

 Setup is unable to connect to SQL Server with the connection information provided. Verify the following:

- The SQL Server and instance names are entered correctly

- The specified SQL Server instance is not configured to use dynamic ports

- If a firewall is enabled on the SQL Server, inbound rules exist to allow connections to the correct ports if not manually create them 

- The account used to run Setup has permissions to connect to the specified SQL server instance

- the account should administrative privileges on the machine

Resolution: 

Open the “SQL Server Configuration manager” and Naviagte to The Protocols of your SQL Instance in the “SQL Server Network Configuration”

Enable “Named Pipes” and “TCP/IP”

Restart the SQL Service Instance within the SQL Server Services:

This seems to be a common issue during the SCCM 2012 setup:  

Verify also that you are running the one of the supported  SQL versions:

- SQL Server 2008 SP2 with Cumulative Update 9
- SQL Server 2008 SP3 with Cumulative Update 4
- SQL Server 2008 R2 with SP1 and Cumulative Update 6

- SQL Express no longer valid for SCCM 2012