Add-on List
Verified with Windows 11 25H2 — updated on July 30, 2026
Supported on: At least Internet Explorer 6.0 in Windows XP with Service Pack 2 or Windows Server 2003 with Service Pack 1
Path in the GPO console
Computer Configuration\Administrative Templates\Windows Components\Internet Explorer\Security Features\Add-on Management User Configuration\Administrative Templates\Windows Components\Internet Explorer\Security Features\Add-on Management Description
This policy setting allows you to manage a list of add-ons to be allowed or denied by Internet Explorer. Add-ons in this case are controls like ActiveX Controls, Toolbars, and Browser Helper Objects (BHOs) which are specifically written to extend or enhance the functionality of the browser or web pages. This list can be used with the 'Deny all add-ons unless specifically allowed in the Add-on List' policy setting, which defines whether add-ons not listed here are assumed to be denied. If you enable this policy setting, you can enter a list of add-ons to be allowed or denied by Internet Explorer. For each entry that you add to the list, enter the following information: Name of the Value - the CLSID (class identifier) for the add-on you wish to add to the list. The CLSID should be in brackets for example, ‘{000000000-0000-0000-0000-0000000000000}'. The CLSID for an add-on can be obtained by reading the OBJECT tag from a Web page on which the add-on is referenced. Value - A number indicating whether Internet Explorer should deny or allow the add-on to be loaded. To specify that an add-on should be denied enter a 0 (zero) into this field. To specify that an add-on should be allowed, enter a 1 (one) into this field. To specify that an add-on should be allowed and also permit the user to manage the add-on through Add-on Manager, enter a 2 (two) into this field. If you disable this policy setting, the list is deleted. The 'Deny all add-ons unless specifically allowed in the Add-on List' policy setting will still determine whether add-ons not in this list are assumed to be denied.
Registry
Software\Microsoft\Windows\CurrentVersion\Policies\Ext Software\Microsoft\Windows\CurrentVersion\Policies\Ext Value name: ListBox_Support_CLSID
Enabled: ListBox_Support_CLSID = 1
Disabled: ListBox_Support_CLSID = 0
MDM / Intune (CSP)
./Device/Vendor/MSFT/Policy/Config/InternetExplorer/AllowAddOnList ./User/Vendor/MSFT/Policy/Config/InternetExplorer/AllowAddOnList Microsoft Learn documentation Mapping data: Microsoft Learn (CC BY 4.0)
Export Builder
BETAConfigure the state, scope and options, then generate .reg, PowerShell, Intune and SCCM outputs — or add the setting to a multi-setting collection.
These exports write the registry — this is not a managed GPO. ⓘ
Applying both scopes creates an ambiguous configuration (computer takes precedence over user). Only do this intentionally.
.reg file
Windows Registry Editor Version 5.00
; Exported from gporais.com
; Policy: Add-on List
; State: Enabled
; Scope: Computer (HKLM)
; Supported on: At least Internet Explorer 6.0 in Windows XP with Service Pack 2 or Windows Server 2003 with Service Pack 1
[HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Policies\Ext]
"ListBox_Support_CLSID"=dword:00000001
[HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Policies\Ext\CLSID]
; List values: enter one value per line in the builder UI.More formats (PowerShell, Intune, SCCM)
PowerShell
# Exported from gporais.com
# Policy: Add-on List
# State: Enabled
# Scope: Computer (HKLM)
# Supported on: At least Internet Explorer 6.0 in Windows XP with Service Pack 2 or Windows Server 2003 with Service Pack 1
$path = 'HKLM:\Software\Microsoft\Windows\CurrentVersion\Policies\Ext'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'ListBox_Support_CLSID' -Value 1 -Type DWord
$path = 'HKLM:\Software\Microsoft\Windows\CurrentVersion\Policies\Ext\CLSID'
New-Item -Path $path -Force | Out-Null
# List values: enter one value per line in the builder UI.Intune XML
OMA-URI: ./Device/Vendor/MSFT/Policy/Config/InternetExplorer/AllowAddOnList
Data type: String
Value:
<enabled/>
<!-- AddOnList: enter one value per line before copying this XML payload. -->Intune Remediation
# === Detection script ===
# Exported from gporais.com
# Policy: Add-on List
# State: Enabled
# Scope: Computer (HKLM)
# Supported on: At least Internet Explorer 6.0 in Windows XP with Service Pack 2 or Windows Server 2003 with Service Pack 1
function Test-RegistryValue {
param(
[Parameter(Mandatory = $true)][string]$Path,
[Parameter(Mandatory = $true)][string]$Name,
[object]$Expected,
[ValidateSet('String', 'DWord', 'MultiString')][string]$Kind = 'String',
[switch]$Absent
)
try {
$item = Get-ItemProperty -LiteralPath $Path -Name $Name -ErrorAction Stop
} catch {
return $Absent.IsPresent
}
if ($Absent.IsPresent) { return $false }
$actual = $item.$Name
if ($Kind -eq 'DWord') { return ([int64]$actual) -eq ([int64]$Expected) }
if ($Kind -eq 'MultiString') {
$actualValues = @($actual)
$expectedValues = @($Expected)
if ($actualValues.Count -ne $expectedValues.Count) { return $false }
for ($i = 0; $i -lt $expectedValues.Count; $i++) {
if ([string]$actualValues[$i] -ne [string]$expectedValues[$i]) { return $false }
}
return $true
}
return [string]$actual -eq [string]$Expected
}
# HKLM:\Software\Microsoft\Windows\CurrentVersion\Policies\Ext\CLSID: List values: enter one value per line in the builder UI.
$checks = @(
(Test-RegistryValue -Path 'HKLM:\Software\Microsoft\Windows\CurrentVersion\Policies\Ext' -Name 'ListBox_Support_CLSID' -Expected 1 -Kind DWord)
)
if ($checks -notcontains $false) {
Write-Output 'Compliant'
exit 0
}
Write-Output 'Non-compliant'
exit 1
# === Remediation script ===
# Exported from gporais.com
# Policy: Add-on List
# State: Enabled
# Scope: Computer (HKLM)
# Supported on: At least Internet Explorer 6.0 in Windows XP with Service Pack 2 or Windows Server 2003 with Service Pack 1
$path = 'HKLM:\Software\Microsoft\Windows\CurrentVersion\Policies\Ext'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'ListBox_Support_CLSID' -Value 1 -Type DWord
$path = 'HKLM:\Software\Microsoft\Windows\CurrentVersion\Policies\Ext\CLSID'
New-Item -Path $path -Force | Out-Null
# List values: enter one value per line in the builder UI.SCCM scripts
# Exported from gporais.com
# Policy: Add-on List
# State: Enabled
# Scope: Computer (HKLM)
# Supported on: At least Internet Explorer 6.0 in Windows XP with Service Pack 2 or Windows Server 2003 with Service Pack 1
# SCCM Configuration Item guidance:
# Create a Configuration Item of type "Setting: Script".
# Discovery script: use the Detection script below.
# Remediation script: use the Remediation script below.
# Compliance rule: the Discovery script output equals 'Compliant'.
# === Detection script ===
# Exported from gporais.com
# Policy: Add-on List
# State: Enabled
# Scope: Computer (HKLM)
# Supported on: At least Internet Explorer 6.0 in Windows XP with Service Pack 2 or Windows Server 2003 with Service Pack 1
function Test-RegistryValue {
param(
[Parameter(Mandatory = $true)][string]$Path,
[Parameter(Mandatory = $true)][string]$Name,
[object]$Expected,
[ValidateSet('String', 'DWord', 'MultiString')][string]$Kind = 'String',
[switch]$Absent
)
try {
$item = Get-ItemProperty -LiteralPath $Path -Name $Name -ErrorAction Stop
} catch {
return $Absent.IsPresent
}
if ($Absent.IsPresent) { return $false }
$actual = $item.$Name
if ($Kind -eq 'DWord') { return ([int64]$actual) -eq ([int64]$Expected) }
if ($Kind -eq 'MultiString') {
$actualValues = @($actual)
$expectedValues = @($Expected)
if ($actualValues.Count -ne $expectedValues.Count) { return $false }
for ($i = 0; $i -lt $expectedValues.Count; $i++) {
if ([string]$actualValues[$i] -ne [string]$expectedValues[$i]) { return $false }
}
return $true
}
return [string]$actual -eq [string]$Expected
}
# HKLM:\Software\Microsoft\Windows\CurrentVersion\Policies\Ext\CLSID: List values: enter one value per line in the builder UI.
$checks = @(
(Test-RegistryValue -Path 'HKLM:\Software\Microsoft\Windows\CurrentVersion\Policies\Ext' -Name 'ListBox_Support_CLSID' -Expected 1 -Kind DWord)
)
if ($checks -notcontains $false) {
Write-Output 'Compliant'
exit 0
}
Write-Output 'Non-compliant'
exit 1
# === Remediation script ===
# Exported from gporais.com
# Policy: Add-on List
# State: Enabled
# Scope: Computer (HKLM)
# Supported on: At least Internet Explorer 6.0 in Windows XP with Service Pack 2 or Windows Server 2003 with Service Pack 1
$path = 'HKLM:\Software\Microsoft\Windows\CurrentVersion\Policies\Ext'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'ListBox_Support_CLSID' -Value 1 -Type DWord
$path = 'HKLM:\Software\Microsoft\Windows\CurrentVersion\Policies\Ext\CLSID'
New-Item -Path $path -Force | Out-Null
# List values: enter one value per line in the builder UI.Building a multi-setting collection? Add this setting and generate combined .reg / PowerShell / GPO scripts.