Allow antimalware service to startup with normal priority
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 Description
This policy setting controls the load priority for the antimalware service. Increasing the load priority will allow for faster service startup, but may impact performance. If you enable or do not configure this setting, the antimalware service will load as a normal priority task. If you disable this setting, the antimalware service will load as a low priority task.
Registry
HKLM
Software\Policies\Microsoft\Windows Defender Value name: AllowFastServiceStartup
Enabled: AllowFastServiceStartup = 1
Disabled: AllowFastServiceStartup = 0
MDM / Intune (CSP)
./Device/Vendor/MSFT/Policy/Config/ADMX_MicrosoftDefenderAntivirus/AllowFastServiceStartup 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: Allow antimalware service to startup with normal priority
; State: Enabled
; Supported on: At least Windows Server 2012, Windows 8 or Windows RT
[HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Windows Defender]
"AllowFastServiceStartup"=dword:00000001More formats (PowerShell, Intune, SCCM)
PowerShell
# Exported from gporais.com
# Policy: Allow antimalware service to startup with normal priority
# State: Enabled
# Supported on: At least Windows Server 2012, Windows 8 or Windows RT
$path = 'HKLM:\Software\Policies\Microsoft\Windows Defender'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'AllowFastServiceStartup' -Value 1 -Type DWordIntune XML
OMA-URI: ./Device/Vendor/MSFT/Policy/Config/ADMX_MicrosoftDefenderAntivirus/AllowFastServiceStartup
Data type: String
Value:
<enabled/>Intune Remediation
# === Detection script ===
# Exported from gporais.com
# Policy: Allow antimalware service to startup with normal priority
# 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
}
$checks = @(
(Test-RegistryValue -Path 'HKLM:\Software\Policies\Microsoft\Windows Defender' -Name 'AllowFastServiceStartup' -Expected 1 -Kind DWord)
)
if ($checks -notcontains $false) {
Write-Output 'Compliant'
exit 0
}
Write-Output 'Non-compliant'
exit 1
# === Remediation script ===
# Exported from gporais.com
# Policy: Allow antimalware service to startup with normal priority
# State: Enabled
# Supported on: At least Windows Server 2012, Windows 8 or Windows RT
$path = 'HKLM:\Software\Policies\Microsoft\Windows Defender'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'AllowFastServiceStartup' -Value 1 -Type DWordSCCM scripts
# Exported from gporais.com
# Policy: Allow antimalware service to startup with normal priority
# 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: Allow antimalware service to startup with normal priority
# 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
}
$checks = @(
(Test-RegistryValue -Path 'HKLM:\Software\Policies\Microsoft\Windows Defender' -Name 'AllowFastServiceStartup' -Expected 1 -Kind DWord)
)
if ($checks -notcontains $false) {
Write-Output 'Compliant'
exit 0
}
Write-Output 'Non-compliant'
exit 1
# === Remediation script ===
# Exported from gporais.com
# Policy: Allow antimalware service to startup with normal priority
# State: Enabled
# Supported on: At least Windows Server 2012, Windows 8 or Windows RT
$path = 'HKLM:\Software\Policies\Microsoft\Windows Defender'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'AllowFastServiceStartup' -Value 1 -Type DWordBuilding a multi-setting collection? Add this setting and generate combined .reg / PowerShell / GPO scripts.