You need to open an elevated PowerShell prompt to run these commands:

Set-MpPreference -EnableNetworkProtection Disabled.Set-MpPreference -EnableNetworkProtection AuditMode.Set-MpPreference -EnableNetworkProtection Enabled.You may use the PowerShell instead to manage the Network protection feature. Audit Mode - This records blocked events but won't block the events.Disabled (default) - The feature is not active.Block - Malicious IP addresses and domains are blocked.

Set the policy to enabled, and assign it one of the available modes:.Load 'Prevent users and apps from accessing dangerous websites' with a double-click.

Navigate to Computer Configuration > Administrative Templates > Windows components > Windows Defender Antivirus > Windows Defender Exploit Guard > Network protection.

Tap on the Windows-key, type gpedit.msc and hit the Enter-key to load the Group Policy Editor.

Note: The Group Policy Editor is not available on Home editions of Windows 10. You can use the Group Policy to enable the Network protection feature on Windows 10 Fall Creators Update (or newer) PCs. System administrators and users may configure the Network protection feature of Windows Defender using policies, PowerShell or MDM CSPs. Tip: check out our previews guides on Controlled Folder Access, Exploit Protection and Attack Surface Reduction for a complete overview of the new security features. The feature is part of Windows Defender Exploit Guard, and it requires that Windows Defender is turned on, and that the security program's real-time protection feature is enabled as well. It extends Windows Defender SmartScreen by blocking outbound (HTTP and HTTPS) traffic connecting to resources that have a low reputation.

Windows defender smartscreen whitelist