Notify antivirus programs when opening attachments: registry value ScanWithAntiVirusUserHKCU\Software\Microsoft\Windows\CurrentVersion\Policies\Attachments

Policy ID: AM_CallIOfficeAntiVirus
Scope: User Configuration
Supported on: At least Windows XP Professional with SP2
Source: Administrative Templates (.admx) for Windows 11 2026 Update (26H2) (version 1.0)
Category: Windows Components › Attachment Manager

Registry

ScanWithAntiVirus

REG_DWORDUser

HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\Attachments Current key

Enabled value: 3
Disabled value: 1

Apply with .reg · CMD · PowerShell

.reg

Windows Registry Editor Version 5.00

[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\Attachments]

; Options (use only one)
; Enabled
"ScanWithAntiVirus"=dword:00000003
; Disabled
"ScanWithAntiVirus"=dword:00000001

CMD

:: Options (use only one)

:: Enabled
reg add "HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\Attachments" /v "ScanWithAntiVirus" /t REG_DWORD /d 3 /f
:: Disabled
reg add "HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\Attachments" /v "ScanWithAntiVirus" /t REG_DWORD /d 1 /f

PowerShell

# Common: create the key
New-Item -Path 'HKCU:\Software\Microsoft\Windows\CurrentVersion\Policies\Attachments' -Force | Out-Null

# Options (use only one)
# Enabled
New-ItemProperty -Path 'HKCU:\Software\Microsoft\Windows\CurrentVersion\Policies\Attachments' -Name 'ScanWithAntiVirus' -PropertyType DWord -Value 3 -Force | Out-Null
# Disabled
New-ItemProperty -Path 'HKCU:\Software\Microsoft\Windows\CurrentVersion\Policies\Attachments' -Name 'ScanWithAntiVirus' -PropertyType DWord -Value 1 -Force | Out-Null