How to: Enable or Disable a Server Network Protocol (SQL Server Configuration Manager)
All network protocols are installed by SQL Server Setup, but may or may not be enabled.
Use SQL Server Configuration Manager to enable or disable network protocols. The Database Engine must be stopped and restarted for the change to take effect.
During setup of SQL Server Express a login is added for the BUILTIN\Users group. This allows all authenticated users of the computer to access the instance of SQL Server Express as a member of the public role. The BUILTIN\Users login can be safely removed to restrict Database Engine access to computer users who have individual logins or are members of other Windows groups with logins.
To enable a server network protocol
In SQL Server Configuration Manager, in the console pane, expand SQL Server Network Configuration.
In the console pane, click Protocols for <instance name>.
In the details pane, right-click the protocol you want to change, and then click Enable or Disable.
In the console pane, click SQL Server Services.
In the details pane, right-click SQL Server (<instance name>), and then click Restart, to stop and restart the SQL Server service.