Turn off Multicast Bootstrap: registry value DisableMulticastBootstrap (IPv6-SiteLocal)ComputerHKLM\Software\policies\Microsoft\Peernet\Pnrp\IPv6-SiteLocal

Policy ID: PNRP_DisableMulticastBootstrap_2
Scope: Computer Configuration
Supported on: At least Windows XP Professional with SP2
Source: Administrative Templates (.admx) for Windows 11 2026 Update (26H2) (version 1.0)
Category: Network › Microsoft Peer-to-Peer Networking Services › Peer Name Resolution Protocol › Site-Local Clouds

Registry

DisableMulticastBootstrap

REG_DWORDComputer

HKLM\Software\policies\Microsoft\Peernet\Pnrp\IPv6-SiteLocal 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\Peernet\Pnrp\IPv6-SiteLocal]

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

CMD

:: Options (use only one)

:: Enabled
reg add "HKLM\Software\policies\Microsoft\Peernet\Pnrp\IPv6-SiteLocal" /v "DisableMulticastBootstrap" /t REG_DWORD /d 1 /f
:: Disabled
reg add "HKLM\Software\policies\Microsoft\Peernet\Pnrp\IPv6-SiteLocal" /v "DisableMulticastBootstrap" /t REG_DWORD /d 0 /f

PowerShell

# Common: create the key
New-Item -Path 'HKLM:\Software\policies\Microsoft\Peernet\Pnrp\IPv6-SiteLocal' -Force | Out-Null

# Options (use only one)
# Enabled
New-ItemProperty -Path 'HKLM:\Software\policies\Microsoft\Peernet\Pnrp\IPv6-SiteLocal' -Name 'DisableMulticastBootstrap' -PropertyType DWord -Value 1 -Force | Out-Null
# Disabled
New-ItemProperty -Path 'HKLM:\Software\policies\Microsoft\Peernet\Pnrp\IPv6-SiteLocal' -Name 'DisableMulticastBootstrap' -PropertyType DWord -Value 0 -Force | Out-Null