Turn on Mapper I/O (LLTDIO) driver: registry value EnableLLTDIO and 3 moreComputerHKLM\Software\Policies\Microsoft\Windows\LLTD

Policy ID: LLTD_EnableLLTDIO
Scope: Computer Configuration
Supported on: At least Windows Vista
Source: Administrative Templates (.admx) for Windows 11 2026 Update (26H2) (version 1.0)
Category: Network › Link-Layer Topology Discovery

Registry

EnableLLTDIO

REG_DWORDComputer

HKLM\Software\Policies\Microsoft\Windows\LLTD 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\Windows\LLTD]

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

CMD

:: Options (use only one)

:: Enabled
reg add "HKLM\Software\Policies\Microsoft\Windows\LLTD" /v "EnableLLTDIO" /t REG_DWORD /d 1 /f
:: Disabled
reg add "HKLM\Software\Policies\Microsoft\Windows\LLTD" /v "EnableLLTDIO" /t REG_DWORD /d 0 /f

PowerShell

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

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

AllowLLTDIOOnDomain

REG_DWORDComputer

HKLM\Software\Policies\Microsoft\Windows\LLTD Current key

Checked: 1
Unchecked: 0
Element: Allow operation while in domain
Value type: REG_DWORD

Apply with .reg · CMD · PowerShell

.reg

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Windows\LLTD]

; Options (use only one)
; Checked
"AllowLLTDIOOnDomain"=dword:00000001
; Unchecked
"AllowLLTDIOOnDomain"=dword:00000000

CMD

:: Options (use only one)

:: Checked
reg add "HKLM\Software\Policies\Microsoft\Windows\LLTD" /v "AllowLLTDIOOnDomain" /t REG_DWORD /d 1 /f
:: Unchecked
reg add "HKLM\Software\Policies\Microsoft\Windows\LLTD" /v "AllowLLTDIOOnDomain" /t REG_DWORD /d 0 /f

PowerShell

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

# Options (use only one)
# Checked
New-ItemProperty -Path 'HKLM:\Software\Policies\Microsoft\Windows\LLTD' -Name 'AllowLLTDIOOnDomain' -PropertyType DWord -Value 1 -Force | Out-Null
# Unchecked
New-ItemProperty -Path 'HKLM:\Software\Policies\Microsoft\Windows\LLTD' -Name 'AllowLLTDIOOnDomain' -PropertyType DWord -Value 0 -Force | Out-Null

AllowLLTDIOOnPublicNet

REG_DWORDComputer

HKLM\Software\Policies\Microsoft\Windows\LLTD Current key

Checked: 1
Unchecked: 0
Element: Allow operation while in public network
Value type: REG_DWORD

Apply with .reg · CMD · PowerShell

.reg

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Windows\LLTD]

; Options (use only one)
; Checked
"AllowLLTDIOOnPublicNet"=dword:00000001
; Unchecked
"AllowLLTDIOOnPublicNet"=dword:00000000

CMD

:: Options (use only one)

:: Checked
reg add "HKLM\Software\Policies\Microsoft\Windows\LLTD" /v "AllowLLTDIOOnPublicNet" /t REG_DWORD /d 1 /f
:: Unchecked
reg add "HKLM\Software\Policies\Microsoft\Windows\LLTD" /v "AllowLLTDIOOnPublicNet" /t REG_DWORD /d 0 /f

PowerShell

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

# Options (use only one)
# Checked
New-ItemProperty -Path 'HKLM:\Software\Policies\Microsoft\Windows\LLTD' -Name 'AllowLLTDIOOnPublicNet' -PropertyType DWord -Value 1 -Force | Out-Null
# Unchecked
New-ItemProperty -Path 'HKLM:\Software\Policies\Microsoft\Windows\LLTD' -Name 'AllowLLTDIOOnPublicNet' -PropertyType DWord -Value 0 -Force | Out-Null

ProhibitLLTDIOOnPrivateNet

REG_DWORDComputer

HKLM\Software\Policies\Microsoft\Windows\LLTD Current key

Checked: 1
Unchecked: 0
Element: Prohibit operation while in private network
Value type: REG_DWORD

Apply with .reg · CMD · PowerShell

.reg

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Windows\LLTD]

; Options (use only one)
; Checked
"ProhibitLLTDIOOnPrivateNet"=dword:00000001
; Unchecked
"ProhibitLLTDIOOnPrivateNet"=dword:00000000

CMD

:: Options (use only one)

:: Checked
reg add "HKLM\Software\Policies\Microsoft\Windows\LLTD" /v "ProhibitLLTDIOOnPrivateNet" /t REG_DWORD /d 1 /f
:: Unchecked
reg add "HKLM\Software\Policies\Microsoft\Windows\LLTD" /v "ProhibitLLTDIOOnPrivateNet" /t REG_DWORD /d 0 /f

PowerShell

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

# Options (use only one)
# Checked
New-ItemProperty -Path 'HKLM:\Software\Policies\Microsoft\Windows\LLTD' -Name 'ProhibitLLTDIOOnPrivateNet' -PropertyType DWord -Value 1 -Force | Out-Null
# Unchecked
New-ItemProperty -Path 'HKLM:\Software\Policies\Microsoft\Windows\LLTD' -Name 'ProhibitLLTDIOOnPrivateNet' -PropertyType DWord -Value 0 -Force | Out-Null