Configure Windows Defender SmartScreen
This computer policy controls Microsoft Defender SmartScreen’s Application Reputation feature, presented in Windows as “Check apps and files.” Windows evaluates programs obtained from the Internet by using security and reputation information.
since 0.9.8.11
Purpose
Show registry keys (2)
HKLM\Software\Policies\Microsoft\Windows\System\EnableSmartScreenHKLM\Software\Policies\Microsoft\Windows\System\ShellSmartScreenLevel
This computer policy controls Microsoft Defender SmartScreen’s Application Reputation feature, presented in Windows as “Check apps and files.” Windows evaluates programs obtained from the Internet by using security and reputation information. Before an unrecognized or known-malicious program runs, SmartScreen displays a warning. Programs that do not appear suspicious do not produce a SmartScreen dialog.
EnableSmartScreen is a REG_DWORD value. A value of 1 turns on SmartScreen for every user of the computer and prevents users from turning it off. A value of 0 turns it off and prevents users from turning it on.
When SmartScreen is enabled, the REG_SZ value ShellSmartScreenLevel selects the warning behavior:
Warndisplays a warning but allows the user to run the program. If the user proceeds, SmartScreen does not warn that user about the same program on later attempts.Blockrepresents the “Warn and prevent bypass” policy option. The dialog does not offer a way to disregard the warning and run the program. SmartScreen displays the warning again on subsequent attempts.
Notes
Security
SmartScreen reduces the risk of users unintentionally running unrecognized or known-malicious programs obtained from the Internet. Block provides stronger protection than Warn because users cannot bypass the warning through the SmartScreen dialog.
Application Reputation is not a complete malware analysis or a general application-control mechanism. This policy does not block a program when SmartScreen does not identify it as suspicious. Turning SmartScreen off removes this additional reputation check and its warnings for affected Internet downloads.
Possible side effects
With Block, legitimate programs that are new, uncommon, or lack an established reputation may also be prevented from running through the SmartScreen dialog. This can affect newly released, internally developed, or rarely used applications.
When the feature is enabled, Windows sends certain information about files and programs to Microsoft so that their reputation can be evaluated.
Notes
This is a computer-scoped policy and applies to every user of the device.
The setting governs app and file checks performed by the Windows shell. It does not configure SmartScreen protection for sites and downloads in Microsoft Edge or the separate App Install Control for software obtained outside the Microsoft Store.
Microsoft documentation
Microsoft Learn: Available Microsoft Defender SmartScreen settings
Microsoft Learn: SmartScreen Policy CSP
Microsoft Learn: ADMX_WindowsExplorer Policy CSP – EnableSmartScreen