A network-related or instance-specific error occurred while establishing a connection to
SQL Server. The server was not found or was not accessible.
Verify that the instance name is correct and that SQL Server is configured
to allow remote connections. (provider: Named Pipes Provider, error: 40 -
Could not open a connection to SQL Server) (Microsoft SQL Server, Error: 53)
The SQL Server client cannot connect to the server. This error could occur because either the client cannot resolve the name of the server or the name of the server is incorrect.
Make sure that you have entered the correct server name on the client, and that you can resolve the name of the server from the client. To check TCP/IP name resolution, you can use the ping command in the Windows operating system.
How do I ping?