Restricted Sites Zone Restricted Protocols: registry value ListBox_Support_4 (RestrictedProtocols)UserHKCU\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\RestrictedProtocols

Policy ID: IESF_NPLRest_RestrictedSitesZone
Scope: Computer Configuration, User Configuration
Supported on: At least Internet Explorer 6.0 in Windows XP with Service Pack 2 or Windows Server 2003 with Service Pack 1
Source: Administrative Templates (.admx) for Windows 11 2026 Update (26H2) (version 1.0)
Category: Windows Components › Internet Explorer › Security Features › Network Protocol Lockdown › Restricted Protocols Per Security Zone

Registry

ListBox_Support_4

REG_DWORDUserComputer

…\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\RestrictedProtocolsHKCU\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\RestrictedProtocols Current key
HKLM\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\RestrictedProtocols

Enabled value: 1
Disabled value: 0

Apply with .reg · CMD · PowerShell

UserPer-account setting

.reg

Windows Registry Editor Version 5.00

[HKEY_CURRENT_USER\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\RestrictedProtocols]

; Options (use only one)
; Enabled
"ListBox_Support_4"=dword:00000001
; Disabled
"ListBox_Support_4"=dword:00000000

CMD

:: Options (use only one)

:: Enabled
reg add "HKCU\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\RestrictedProtocols" /v "ListBox_Support_4" /t REG_DWORD /d 1 /f
:: Disabled
reg add "HKCU\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\RestrictedProtocols" /v "ListBox_Support_4" /t REG_DWORD /d 0 /f

PowerShell

# Common: create the key
New-Item -Path 'HKCU:\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\RestrictedProtocols' -Force | Out-Null

# Options (use only one)
# Enabled
New-ItemProperty -Path 'HKCU:\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\RestrictedProtocols' -Name 'ListBox_Support_4' -PropertyType DWord -Value 1 -Force | Out-Null
# Disabled
New-ItemProperty -Path 'HKCU:\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\RestrictedProtocols' -Name 'ListBox_Support_4' -PropertyType DWord -Value 0 -Force | Out-Null

ComputerMachine-wide setting

.reg

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\RestrictedProtocols]

; Options (use only one)
; Enabled
"ListBox_Support_4"=dword:00000001
; Disabled
"ListBox_Support_4"=dword:00000000

CMD

:: Options (use only one)

:: Enabled
reg add "HKLM\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\RestrictedProtocols" /v "ListBox_Support_4" /t REG_DWORD /d 1 /f
:: Disabled
reg add "HKLM\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\RestrictedProtocols" /v "ListBox_Support_4" /t REG_DWORD /d 0 /f

PowerShell

# Common: create the key
New-Item -Path 'HKLM:\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\RestrictedProtocols' -Force | Out-Null

# Options (use only one)
# Enabled
New-ItemProperty -Path 'HKLM:\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\RestrictedProtocols' -Name 'ListBox_Support_4' -PropertyType DWord -Value 1 -Force | Out-Null
# Disabled
New-ItemProperty -Path 'HKLM:\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\RestrictedProtocols' -Name 'ListBox_Support_4' -PropertyType DWord -Value 0 -Force | Out-Null

(list values)

REG_SZComputerUser

…\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\RestrictedProtocols\4HKLM\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\RestrictedProtocols\4
HKCU\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\RestrictedProtocols\4

Enabled value: Depends on the option value
Element: Enter restricted protocols for this zone.
Value type: REG_SZ
Add to existing value: true

Apply with .reg · CMD · PowerShell

ComputerMachine-wide setting

.reg

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\RestrictedProtocols\4]
"<enter value>"="<enter value>"

CMD

reg add "HKLM\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\RestrictedProtocols\4" /v "<enter value>" /t REG_SZ /d "<enter value>" /f

PowerShell

New-Item -Path 'HKLM:\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\RestrictedProtocols\4' -Force | Out-Null
New-ItemProperty -Path 'HKLM:\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\RestrictedProtocols\4' -Name '<enter value>' -PropertyType String -Value '<enter value>' -Force | Out-Null

UserPer-account setting

.reg

Windows Registry Editor Version 5.00

[HKEY_CURRENT_USER\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\RestrictedProtocols\4]
"<enter value>"="<enter value>"

CMD

reg add "HKCU\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\RestrictedProtocols\4" /v "<enter value>" /t REG_SZ /d "<enter value>" /f

PowerShell

New-Item -Path 'HKCU:\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\RestrictedProtocols\4' -Force | Out-Null
New-ItemProperty -Path 'HKCU:\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\RestrictedProtocols\4' -Name '<enter value>' -PropertyType String -Value '<enter value>' -Force | Out-Null