I tried run SQLCMD from the command line:
sqlcmd -E -S MSSQLSERVER
Sqlcmd: Error: Microsoft ODBC Driver 11for SQL Server : Named Pipes Provider:
Could notopen a connection to SQL Server [67]..
Sqlcmd: Error: Microsoft ODBC Driver 11for SQL Server : Login timeout expired.
Sqlcmd: Error: Microsoft ODBC Driver 11for SQL Server :
A network-related or instance-specific error has occurredwhile establishing a connection to SQL Server. Server isnot found ornot accessible.Checkif instance name is correct andif SQL Server is configured to allow remote connections.For more information see SQL Server Books Online..