Do not allow Windows Messenger to be run: registry value PreventRun (HKLM Client)ComputerHKLM\Software\Policies\Microsoft\Messenger\Client

Policy ID: WinMSG_NoWindowsMsg_Comp
Scope: Computer Configuration
Supported on: At least Windows Server 2003 operating systems or Windows XP Professional
Source: Administrative Templates (.admx) for Windows 11 2026 Update (26H2) (version 1.0)
Category: Windows Components › Windows Messenger

Registry

PreventRun

REG_DWORDComputer

HKLM\Software\Policies\Microsoft\Messenger\Client Current key

Enabled value: 1
Disabled value: 0

Apply with .reg · CMD · PowerShell

.reg

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Messenger\Client]

; Options (use only one)
; Enabled
"PreventRun"=dword:00000001
; Disabled
"PreventRun"=dword:00000000

CMD

:: Options (use only one)

:: Enabled
reg add "HKLM\Software\Policies\Microsoft\Messenger\Client" /v "PreventRun" /t REG_DWORD /d 1 /f
:: Disabled
reg add "HKLM\Software\Policies\Microsoft\Messenger\Client" /v "PreventRun" /t REG_DWORD /d 0 /f

PowerShell

# Common: create the key
New-Item -Path 'HKLM:\Software\Policies\Microsoft\Messenger\Client' -Force | Out-Null

# Options (use only one)
# Enabled
New-ItemProperty -Path 'HKLM:\Software\Policies\Microsoft\Messenger\Client' -Name 'PreventRun' -PropertyType DWord -Value 1 -Force | Out-Null
# Disabled
New-ItemProperty -Path 'HKLM:\Software\Policies\Microsoft\Messenger\Client' -Name 'PreventRun' -PropertyType DWord -Value 0 -Force | Out-Null