Show security warning for potentially unsafe files
The `1806` `REG_DWORD` value controls the URL security action for opening executable files and other files classified as potentially unsafe when they originate from the Internet zone.
since 0.9.8.11
Purpose
Show registry keys (2)
HKLM\Software\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\3\1806HKCU\Software\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\3\1806
The 1806 REG_DWORD value controls the URL security action for opening executable files and other files classified as potentially unsafe when they originate from the Internet zone. Zone number 3 represents the Internet zone.
The supported policy values have these effects:
0: The file may open without an “Open File – Security Warning” prompt.1: Windows displays a security warning before opening the file and lets the user decide whether to proceed.3: Windows prevents the file from opening.
When the policy is not configured, this behavior is not enforced through the policy value. The Windows default for the Internet zone is Prompt.
The value under HKLM represents the device policy scope, while the value under HKCU represents the user policy scope. Both control the same security-zone action within their respective scopes.
Notes
Additional effects
Microsoft Edge still consults Windows Security Zones for some file-download decisions. If launching potentially unsafe files is disabled for the applicable zone, the Microsoft Edge download manager can block downloads from sites in that zone. Internet Explorer mode tabs also evaluate Windows Security Zone settings.
Security
A value of 0 removes a warning that can help prevent users from unintentionally launching malicious files obtained from the Internet zone. It therefore reduces a defense-in-depth safeguard.
A value of 1 preserves the warning but still permits the user to open the file after confirmation. A value of 3 blocks launches governed by this URL security action.
This setting is not a replacement for malware scanning and does not grant additional user rights or elevated privileges. File permissions, User Account Control, Microsoft Defender, SmartScreen, and other security controls can continue to apply independently.
Possible side effects
A value of 3 can prevent legitimate applications and other affected files from opening. It can also cause Microsoft Edge to block downloads from Internet-zone sites. A value of 1 introduces an additional prompt when affected files are opened.
Notes
This setting is part of the legacy Windows and Internet Explorer URL Security Zones infrastructure. Current versions of Microsoft Edge use that infrastructure only for selected behaviors, particularly file downloads and Internet Explorer mode.
Microsoft's current reference lists the corresponding ADMX-backed policy for both device and user scope on Windows 10, version 1709 and later.
Microsoft documentation
Microsoft Learn: Per-site configuration by policy
Microsoft Learn: URL Policy Flags