Automatic prompting for file downloads
This policy controls how the Internet zone handles file downloads that were not initiated by an explicit user action, such as a mouse click or keystroke.
since 0.9.8.11
Purpose
Show registry keys (2)
HKLM\Software\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\3\2200HKCU\Software\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\3\2200
This policy controls how the Internet zone handles file downloads that were not initiated by an explicit user action, such as a mouse click or keystroke.
The 2200 value is a REG_DWORD representing the URLACTION_AUTOMATIC_DOWNLOAD_UI URL action:
- A value of
0displays a file download dialog immediately when an automatic download is attempted. - A value of
3initially blocks a download that was not initiated by the user. The Notification bar is displayed instead of the dialog, and the user can use it to permit the download prompt.
Downloads explicitly initiated by the user continue to produce a file download dialog regardless of this setting.
Notes
Security
A value of 0 allows a website in the Internet zone to open a download dialog without a preceding user action. It does not silently save the file or bypass the user's confirmation. However, unsolicited dialogs can make it easier to persuade a user to accept an unexpected or malicious download.
A value of 3 requires an additional action through the Notification bar. This reduces the risk of accepting an automatically initiated download merely by confirming a dialog that appeared unexpectedly. It does not prohibit the download completely because the user can still permit the prompt from the Notification bar.
Possible side effects
With a value of 3, legacy websites and web applications that initiate downloads automatically require an additional user interaction. An expected download may therefore initially appear to have been blocked.
With a value of 0, websites can display unsolicited download dialogs and interrupt the user's workflow.
Notes
The HKLM and HKCU keys represent the computer and user policy scopes, respectively. Zone number 3 applies only to the Internet zone. Content assigned to another security zone uses that zone's corresponding settings.
This setting is not a general control for allowing or prohibiting file downloads. It governs only the user interface and initial handling of download attempts that were not initiated by the user. Microsoft documents the underlying URL action as part of the Internet Explorer security-zone model and as dependent on the FEATURE_RESTRICT_FILEDOWNLOAD feature control.
Microsoft documentation
Microsoft Learn: InternetExplorer Policy CSP – InternetZoneAllowAutomaticPromptingForFileDownloads
Microsoft Learn: URL Action Flags – URLACTION_AUTOMATIC_DOWNLOAD_UI