Block processing of S/MIME encrypted messages by certain connected experiences: registry value smimedisabledatauploadUserHKCU\software\policies\microsoft\office\16.0\common\privacy

Policy ID: L_SMimeDisableDataUpload
Scope: User Configuration
Supported on: At least Windows Server 2008 R2 or Windows 7
Source: Microsoft 365 Apps / Office Administrative Templates (version 5568.1000)
Category: Microsoft Outlook 2016 › Security › Trust Center

Registry

smimedisabledataupload

REG_DWORDUser

HKCU\software\policies\microsoft\office\16.0\common\privacy Current key

Enabled value: 2
Disabled value: 1

Apply with .reg · CMD · PowerShell

.reg

Windows Registry Editor Version 5.00

[HKEY_CURRENT_USER\software\policies\microsoft\office\16.0\common\privacy]

; Options (use only one)
; Enabled
"smimedisabledataupload"=dword:00000002
; Disabled
"smimedisabledataupload"=dword:00000001

CMD

:: Options (use only one)

:: Enabled
reg add "HKCU\software\policies\microsoft\office\16.0\common\privacy" /v "smimedisabledataupload" /t REG_DWORD /d 2 /f
:: Disabled
reg add "HKCU\software\policies\microsoft\office\16.0\common\privacy" /v "smimedisabledataupload" /t REG_DWORD /d 1 /f

PowerShell

# Common: create the key
New-Item -Path 'HKCU:\software\policies\microsoft\office\16.0\common\privacy' -Force | Out-Null

# Options (use only one)
# Enabled
New-ItemProperty -Path 'HKCU:\software\policies\microsoft\office\16.0\common\privacy' -Name 'smimedisabledataupload' -PropertyType DWord -Value 2 -Force | Out-Null
# Disabled
New-ItemProperty -Path 'HKCU:\software\policies\microsoft\office\16.0\common\privacy' -Name 'smimedisabledataupload' -PropertyType DWord -Value 1 -Force | Out-Null