Extension Exclusions
Verified with Windows 11 25H2 — updated on July 30, 2026
Supported on: At least Windows Server 2012, Windows 8 or Windows RT
Path in the GPO console
Computer Configuration\Administrative Templates\Windows Components\Microsoft Defender Antivirus\Exclusions Description
This policy setting allows you specify a list of file types that should be excluded from scheduled, custom, and real-time scanning. File types should be added under the Options for this setting. Each entry must be listed as a name value pair, where the name should be a string representation of the file type extension (such as "obj" or "lib"). The value is not used and it is recommended that this be set to 0.
Registry
HKLM
Software\Policies\Microsoft\Windows Defender\Exclusions Value name: Exclusions_Extensions
MDM / Intune (CSP)
./Device/Vendor/MSFT/Policy/Config/ADMX_MicrosoftDefenderAntivirus/Exclusions_Extensions Multiple CSP matches are possible; the first one was selected.
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. ⓘ
.reg file
Windows Registry Editor Version 5.00
; Exported from gporais.com
; Policy: Extension Exclusions
; State: Enabled
; Supported on: At least Windows Server 2012, Windows 8 or Windows RT
[HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Windows Defender\Exclusions]
"Exclusions_Extensions"=dword:00000001
[HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Windows Defender\Exclusions\Extensions]
; List values: enter one value per line in the builder UI.More formats (PowerShell, Intune, SCCM)
PowerShell
# Exported from gporais.com
# Policy: Extension Exclusions
# State: Enabled
# Supported on: At least Windows Server 2012, Windows 8 or Windows RT
$path = 'HKLM:\Software\Policies\Microsoft\Windows Defender\Exclusions'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'Exclusions_Extensions' -Value 1 -Type DWord
$path = 'HKLM:\Software\Policies\Microsoft\Windows Defender\Exclusions\Extensions'
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/ADMX_MicrosoftDefenderAntivirus/Exclusions_Extensions
Data type: String
Value:
<enabled/>
<!-- Exclusions_ExtensionsList: enter one value per line before copying this XML payload. -->Intune Remediation
# === Detection script ===
# Exported from gporais.com
# Policy: Extension Exclusions
# State: Enabled
# Supported on: At least Windows Server 2012, Windows 8 or Windows RT
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\Policies\Microsoft\Windows Defender\Exclusions\Extensions: List values: enter one value per line in the builder UI.
$checks = @(
(Test-RegistryValue -Path 'HKLM:\Software\Policies\Microsoft\Windows Defender\Exclusions' -Name 'Exclusions_Extensions' -Expected 1 -Kind DWord)
)
if ($checks -notcontains $false) {
Write-Output 'Compliant'
exit 0
}
Write-Output 'Non-compliant'
exit 1
# === Remediation script ===
# Exported from gporais.com
# Policy: Extension Exclusions
# State: Enabled
# Supported on: At least Windows Server 2012, Windows 8 or Windows RT
$path = 'HKLM:\Software\Policies\Microsoft\Windows Defender\Exclusions'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'Exclusions_Extensions' -Value 1 -Type DWord
$path = 'HKLM:\Software\Policies\Microsoft\Windows Defender\Exclusions\Extensions'
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: Extension Exclusions
# State: Enabled
# Supported on: At least Windows Server 2012, Windows 8 or Windows RT
# 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: Extension Exclusions
# State: Enabled
# Supported on: At least Windows Server 2012, Windows 8 or Windows RT
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\Policies\Microsoft\Windows Defender\Exclusions\Extensions: List values: enter one value per line in the builder UI.
$checks = @(
(Test-RegistryValue -Path 'HKLM:\Software\Policies\Microsoft\Windows Defender\Exclusions' -Name 'Exclusions_Extensions' -Expected 1 -Kind DWord)
)
if ($checks -notcontains $false) {
Write-Output 'Compliant'
exit 0
}
Write-Output 'Non-compliant'
exit 1
# === Remediation script ===
# Exported from gporais.com
# Policy: Extension Exclusions
# State: Enabled
# Supported on: At least Windows Server 2012, Windows 8 or Windows RT
$path = 'HKLM:\Software\Policies\Microsoft\Windows Defender\Exclusions'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'Exclusions_Extensions' -Value 1 -Type DWord
$path = 'HKLM:\Software\Policies\Microsoft\Windows Defender\Exclusions\Extensions'
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.