6. Click New Query in SQL Server Management Studio and type select @@servername to verify everything is correct and you have successfully changed the sql server name.

Now, enter your SQL Server's name and choose the authentication type that you want to use. If necessary, enter the credentials to be used for SQL Server authentication.

I'm trying to start/stop MS SQL Service on various DB servers (locally) but we don't always know the name of the instance (Always only 1 SQL Server running on a single server).