Allow companion device for secondary authentication: registry value AllowSecondaryAuthenticationDeviceComputerHKLM\SOFTWARE\Policies\Microsoft\SecondaryAuthenticationFactor

Policy ID: MSSecondaryAuthFactor_AllowSecondaryAuthenticationDevice
Scope: Computer Configuration
Supported on: At least Windows Server 2016, Windows 10
Source: Administrative Templates (.admx) for Windows 11 2026 Update (26H2) (version 1.0)
Category: Windows Components › Microsoft Secondary Authentication Factor

Registry

AllowSecondaryAuthenticationDevice

REG_DWORDComputer

HKLM\SOFTWARE\Policies\Microsoft\SecondaryAuthenticationFactor 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\SecondaryAuthenticationFactor]

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

CMD

:: Options (use only one)

:: Enabled
reg add "HKLM\SOFTWARE\Policies\Microsoft\SecondaryAuthenticationFactor" /v "AllowSecondaryAuthenticationDevice" /t REG_DWORD /d 1 /f
:: Disabled
reg add "HKLM\SOFTWARE\Policies\Microsoft\SecondaryAuthenticationFactor" /v "AllowSecondaryAuthenticationDevice" /t REG_DWORD /d 0 /f

PowerShell

# Common: create the key
New-Item -Path 'HKLM:\SOFTWARE\Policies\Microsoft\SecondaryAuthenticationFactor' -Force | Out-Null

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