This policy setting allows you to control whether anyone can interact with available networks UI on the logon screen. The recommended state for this setting is: Enabled. Rationale: An unauthorized user could disconnect the PC from the network or can connect the PC to other available networks without signing into Windows. Impact: The PC's network connectivity state cannot be changed without signing into Windows.
To establish the recommended configuration via GP, set the following UI path to Enabled: Computer Configuration\Policies\Administrative Templates\System\Logon\Do not display network selection UI Note: This Group Policy path may not exist by default. It is provided by the Group Policy template Logon.admx/adml that is included with the Microsoft Windows 8.1 & Server 2012 R2 Administrative Templates (or newer). Default Value: Disabled. (Any user can disconnect the PC from the network or can connect the PC to other available networks without signing into Windows.)