创建管理中心用127.0.0.1提示报错

创建管理中心时，数据库服务器选127.0.0.1，测试不通过，提示：连接数据库失败！
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)

但是我在数据库的配置服务器那里启动了TCP/IP，原因？