Windows Components › Application Compatibility
Turn off Application Compatibility Engine
Supported on At least Windows Server 2003
What it does
This policy controls the state of the application compatibility engine in the system. The engine is part of the loader and looks through a compatibility database every time an application is started on the system. If a match for the application is found it provides either run-time solutions or compatibility fixes, or displays an Application Help message if the application has a know problem. Turning off the application compatibility engine will boost system performance. However, this will degrade the compatibility of many popular legacy applications, and will not block known incompatible applications from installing. (For Instance: This may result in a blue screen if an old anti-virus application is installed.) The Windows Resource Protection and User Account Control features of Windows use the application compatibility engine to provide mitigations for application problems. If the engine is turned off, these mitigations will not be applied to applications and their installers and these applications may fail to install or run properly. This option is useful to server administrators who require faster performance and are aware of the compatibility of the applications they are using. It is particularly useful for a web server where applications may be launched several hundred times a second, and the performance of the loader is essential. NOTE: Many system processes cache the value of this setting for performance reasons. If you make changes to this setting, please reboot to ensure that your system accurately reflects those changes.
What it writes
- Hive
- HKEY_LOCAL_MACHINE
- Registry key
Software\Policies\Microsoft\Windows\AppCompat- Value name
DisableEngine- When enabled
- DWORD 1
- When disabled
- value removed
Why it needs changes for Intune
- Policy references a Windows supportedOn definition.
- ADMX-INTUNE-WINDOWS-SUPPORTEDON-REFERENCE
In Intune
Native Intune setting: Yes — Policy CSP
./Device/Vendor/MSFT/Policy/Config/ADMX_AppCompat/AppCompatTurnOffEngineADMX_AppCompat on Microsoft LearnADMX-backed: Windows ships this template, so it is set with the template's own values, without an import.Windows builds listed: 10.0.22000, 10.0.19043.1202, 10.0.19042.1202, 10.0.19041.1202.
From Microsoft's Policy CSP DDF files (DDF v2 Files, February 2026), read 18 Oct 2026.
Configure and deploy
Choose a state; the output below is generated from the template for exactly that.
Enabled · Computer · template defaults
Registry file (.reg)
Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Windows\AppCompat]
"DisableEngine"=dword:00000001
PowerShell
$ErrorActionPreference = 'Stop'
function Set-RegistryValue {
param(
[Parameter(Mandatory = $true)][string] $Path,
[Parameter(Mandatory = $true)][string] $Name,
[Parameter(Mandatory = $true)][string] $PropertyType,
[Parameter(Mandatory = $true)][object] $Value
)
if (-not (Test-Path -LiteralPath $Path)) {
New-Item -Path $Path -Force | Out-Null
}
New-ItemProperty -LiteralPath $Path -Name $Name -PropertyType $PropertyType -Value $Value -Force | Out-Null
}
function Remove-RegistryValue {
param(
[Parameter(Mandatory = $true)][string] $Path,
[Parameter(Mandatory = $true)][string] $Name
)
if (Test-Path -LiteralPath $Path) {
Remove-ItemProperty -LiteralPath $Path -Name $Name -Force -ErrorAction SilentlyContinue
}
}
function Clear-RegistryKeyValues {
param(
[Parameter(Mandatory = $true)][string] $Path
)
if (-not (Test-Path -LiteralPath $Path)) {
return
}
foreach ($propertyName in (Get-Item -LiteralPath $Path).Property) {
Remove-ItemProperty -LiteralPath $Path -Name $propertyName -Force -ErrorAction SilentlyContinue
}
}
# Policy: Turn off Application Compatibility Engine
# Name: AppCompatTurnOffEngine
# Scope: Machine
# State: Enabled
# Source: AppCompat.admx
Set-RegistryValue -Path 'Registry::HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Windows\AppCompat' -Name 'DisableEngine' -PropertyType 'DWord' -Value 1
These deployment candidates come from the ADMX template; they are separate from the native CSP mapping above.
- The OMA-URI is an inferred ADMX-backed Policy CSP candidate derived from the source ADMX file name and policy name.
- Some Microsoft policies use built-in Policy CSP pages whose area names don't match the ADMX file name, so verify the candidate against Microsoft Learn before deployment.
ADMX profile candidate (OMA-URI)
./Device/Vendor/MSFT/Policy/Config/ADMX_AppCompat/AppCompatTurnOffEngineADMX SyncML candidate
<SyncML xmlns="SYNCML:SYNCML1.2">
<SyncBody>
<Replace>
<CmdID>1</CmdID>
<Item>
<Meta>
<Format>chr</Format>
<Type>text/plain</Type>
</Meta>
<Target>
<LocURI>./Device/Vendor/MSFT/Policy/Config/ADMX_AppCompat/AppCompatTurnOffEngine</LocURI>
</Target>
<Data><enabled/></Data>
</Item>
</Replace>
<Final/>
</SyncBody>
</SyncML>Intune remediation scripts
Detection
$ErrorActionPreference = 'Stop'
$reasons = [System.Collections.Generic.List[string]]::new()
function Test-RegistryValueExists {
param(
[Parameter(Mandatory = $true)][string] $Path,
[Parameter(Mandatory = $true)][string] $Name
)
if (-not (Test-Path -LiteralPath $Path)) {
return $false
}
return $null -ne (Get-ItemProperty -LiteralPath $Path -Name $Name -ErrorAction SilentlyContinue)
}
function Test-RegistryValueEquals {
param(
[Parameter(Mandatory = $true)][string] $Path,
[Parameter(Mandatory = $true)][string] $Name,
[Parameter(Mandatory = $true)][string] $Kind,
[Parameter(Mandatory = $true)][object] $Expected
)
if (-not (Test-Path -LiteralPath $Path)) {
return $false
}
$valueObject = Get-ItemProperty -LiteralPath $Path -Name $Name -ErrorAction SilentlyContinue
if ($null -eq $valueObject) {
return $false
}
$actual = $valueObject.$Name
switch ($Kind) {
'String' { return [string]$actual -ceq [string]$Expected }
'ExpandString' { return [string]$actual -ceq [string]$Expected }
'DWord' { return [uint32]$actual -eq [uint32]$Expected }
'QWord' { return [uint64]$actual -eq [uint64]$Expected }
'MultiString' {
$actualArray = @($actual)
$expectedArray = @($Expected)
if ($actualArray.Count -ne $expectedArray.Count) { return $false }
for ($index = 0; $index -lt $actualArray.Count; $index++) {
if ([string]$actualArray[$index] -cne [string]$expectedArray[$index]) { return $false }
}
return $true
}
'Binary' {
$actualArray = [byte[]]$actual
$expectedArray = [byte[]]$Expected
if ($actualArray.Length -ne $expectedArray.Length) { return $false }
for ($index = 0; $index -lt $actualArray.Length; $index++) {
if ($actualArray[$index] -ne $expectedArray[$index]) { return $false }
}
return $true
}
default { return [string]$actual -ceq [string]$Expected }
}
}
# Policy: Turn off Application Compatibility Engine
# Name: AppCompatTurnOffEngine
# Scope: Machine
# State: Enabled
# Source: AppCompat.admx
$isMatch = Test-RegistryValueEquals -Path 'Registry::HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Windows\AppCompat' -Name 'DisableEngine' -Kind 'DWord' -Expected 1
if (-not $isMatch) {
$reasons.Add('Value mismatch: HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Windows\AppCompat\DisableEngine') | Out-Null
}
if ($reasons.Count -eq 0) {
Write-Output 'Compliant'
exit 0
}
$reasons | ForEach-Object { Write-Output $_ }
exit 1
Remediation
$ErrorActionPreference = 'Stop'
function Set-RegistryValue {
param(
[Parameter(Mandatory = $true)][string] $Path,
[Parameter(Mandatory = $true)][string] $Name,
[Parameter(Mandatory = $true)][string] $PropertyType,
[Parameter(Mandatory = $true)][object] $Value
)
if (-not (Test-Path -LiteralPath $Path)) {
New-Item -Path $Path -Force | Out-Null
}
New-ItemProperty -LiteralPath $Path -Name $Name -PropertyType $PropertyType -Value $Value -Force | Out-Null
}
function Remove-RegistryValue {
param(
[Parameter(Mandatory = $true)][string] $Path,
[Parameter(Mandatory = $true)][string] $Name
)
if (Test-Path -LiteralPath $Path) {
Remove-ItemProperty -LiteralPath $Path -Name $Name -Force -ErrorAction SilentlyContinue
}
}
function Clear-RegistryKeyValues {
param(
[Parameter(Mandatory = $true)][string] $Path
)
if (-not (Test-Path -LiteralPath $Path)) {
return
}
foreach ($propertyName in (Get-Item -LiteralPath $Path).Property) {
Remove-ItemProperty -LiteralPath $Path -Name $propertyName -Force -ErrorAction SilentlyContinue
}
}
# Policy: Turn off Application Compatibility Engine
# Name: AppCompatTurnOffEngine
# Scope: Machine
# State: Enabled
# Source: AppCompat.admx
Set-RegistryValue -Path 'Registry::HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Windows\AppCompat' -Name 'DisableEngine' -PropertyType 'DWord' -Value 1
History 5 retained releases
- 22H2 · 1.015 Jul 2024
- Already present in the first release ChangeIntel keeps.
4 later releases left it unchanged.
Template
- Internal name
AppCompatTurnOffEngine- Namespace
Microsoft.Policies.ApplicationCompatibility- Template file
AppCompat.admx- Release
- Windows 11 25H2 · 1.0 · file set
de4e49983ebd651f…
Definition, editor controls and support
Definition
<policy class="Machine" displayName="$(string.AppCompatTurnOffEngine)" explainText="$(string.AppCompat_TurnOffEngine_Help)" key="Software\Policies\Microsoft\Windows\AppCompat" name="AppCompatTurnOffEngine" valueName="DisableEngine" xmlns="http://schemas.microsoft.com/GroupPolicy/2006/07/PolicyDefinitions">
<parentCategory ref="Microsoft.Policies.ApplicationCompatibility:AppCompat" />
<supportedOn ref="Microsoft.Policies.Windows:SUPPORTED_WindowsNET" />
</policy>Editor controls
Supported platforms and category
Microsoft.Policies.ApplicationCompatibility:category:AppCompat
<category displayName="$(string.AppCompat)" name="AppCompat" xmlns="http://schemas.microsoft.com/GroupPolicy/2006/07/PolicyDefinitions">
<parentCategory ref="Microsoft.Policies.Windows:WindowsComponents" />
</category>
Microsoft.Policies.Products:product:MicrosoftWindows
sha256:4b3cb6917b5e5b7cd142c0157f10882786b3e9ee67c29fd7b8f4c6cb2eec5fe7
Microsoft.Policies.Windows:category:WindowsComponents
<category displayName="$(string.WindowsComponents)" explainText="$(string.WindowsComponents_Help)" name="WindowsComponents" xmlns="http://schemas.microsoft.com/GroupPolicy/2006/07/PolicyDefinitions" />
Microsoft.Policies.Windows:definition:SUPPORTED_WindowsNET
<definition displayName="$(string.SUPPORTED_WindowsNET)" name="SUPPORTED_WindowsNET" xmlns="http://schemas.microsoft.com/GroupPolicy/2006/07/PolicyDefinitions">
<or>
<range minVersionIndex="3" ref="Microsoft.Policies.Products:MicrosoftWindows" />
</or>
</definition>
Microsoft.Policies.ApplicationCompatibility:category:AppCompat
<category displayName="$(string.AppCompat)" name="AppCompat" xmlns="http://schemas.microsoft.com/GroupPolicy/2006/07/PolicyDefinitions">
<parentCategory ref="Microsoft.Policies.Windows:WindowsComponents" />
</category>
<strings><string id="Microsoft.Policies.ApplicationCompatibility:AppCompat">Application Compatibility</string></strings>
Microsoft.Policies.Products:product:MicrosoftWindows
<product displayName="$(string.MicrosoftWindows)" name="MicrosoftWindows" xmlns="http://schemas.microsoft.com/GroupPolicy/2006/07/PolicyDefinitions">
<majorVersion displayName="$(string.MicrosoftWindows2000)" name="MicrosoftWindows2000" versionIndex="1">
<minorVersion displayName="$(string.MicrosoftWindows2000_RTM)" name="MicrosoftWindows2000_RTM" versionIndex="0" />
<minorVersion displayName="$(string.MicrosoftWindows2000_SP1)" name="MicrosoftWindows2000_SP1" versionIndex="1" />
<minorVersion displayName="$(string.MicrosoftWindows2000_SP2)" name="MicrosoftWindows2000_SP2" versionIndex="2" />
<minorVersion displayName="$(string.MicrosoftWindows2000_SP3)" name="MicrosoftWindows2000_SP3" versionIndex="3" />
<minorVersion displayName="$(string.MicrosoftWindows2000_SP4)" name="MicrosoftWindows2000_SP4" versionIndex="4" />
</majorVersion>
<majorVersion displayName="$(string.MicrosoftWindowsXP)" name="MicrosoftWindowsXP" versionIndex="2">
<minorVersion displayName="$(string.MicrosoftWindowsXP_RTM)" name="MicrosoftWindowsXP_RTM" versionIndex="0" />
<minorVersion displayName="$(string.MicrosoftWindowsXP_SP1)" name="MicrosoftWindowsXP_SP1" versionIndex="1" />
<minorVersion displayName="$(string.MicrosoftWindowsXP_SP2)" name="MicrosoftWindowsXP_SP2" versionIndex="2" />
</majorVersion>
<majorVersion displayName="$(string.MicrosoftWindowsServer2003)" name="MicrosoftWindowsServer2003" versionIndex="3">
<minorVersion displayName="$(string.MicrosoftWindowsServer2003_RTM)" name="MicrosoftWindowsServer2003_RTM" versionIndex="0" />
<minorVersion displayName="$(string.MicrosoftWindowsServer2003_SP1)" name="MicrosoftWindowsServer2003_SP1" versionIndex="1" />
<minorVersion displayName="$(string.MicrosoftWindowsServer2003_R2)" name="MicrosoftWindowsServer2003_R2" versionIndex="2" />
<minorVersion displayName="$(string.MicrosoftWindowsServer2003_SP2)" name="MicrosoftWindowsServer2003_SP2" versionIndex="3" />
</majorVersion>
<majorVersion displayName="$(string.MicrosoftWindowsVista)" name="MicrosoftWindowsVista" versionIndex="4">
<minorVersion displayName="$(string.MicrosoftWindowsVista_RTM)" name="MicrosoftWindowsVista_RTM" versionIndex="0" />
<minorVersion displayName="$(string.MicrosoftWindowsVista_SP1)" name="MicrosoftWindowsVista_SP1" versionIndex="1" />
</majorVersion>
<majorVersion displayName="$(string.WindowsServer2008)" name="WindowsServer2008" versionIndex="5">
<minorVersion displayName="$(string.WindowsServer2008_RTM)" name="WindowsServer2008_RTM" versionIndex="0" />
<minorVersion displayName="$(string.WindowsServer2008_R2)" name="WindowsServer2008_R2" versionIndex="1" />
</majorVersion>
<majorVersion displayName="$(string.MicrosoftWindows7)" name="MicrosoftWindows7" versionIndex="6">
<minorVersion displayName="$(string.MicrosoftWindows7_RTM)" name="MicrosoftWindows7_RTM" versionIndex="0" />
</majorVersion>
<majorVersion displayName="$(string.MicrosoftWindowsServer8)" name="MicrosoftWindowsServer8" versionIndex="7">
<minorVersion displayName="$(string.MicrosoftWindowsServer8_RTM)" name="MicrosoftWindowsServer8_RTM" versionIndex="0" />
</majorVersion>
<majorVersion displayName="$(string.MicrosoftWindows8)" name="MicrosoftWindows8" versionIndex="8">
<minorVersion displayName="$(string.MicrosoftWindows8_RTM)" name="MicrosoftWindows8_RTM" versionIndex="0" />
</majorVersion>
<majorVersion displayName="$(string.MicrosoftWindows_RT)" name="MicrosoftWindows_RT" versionIndex="9">
<minorVersion displayName="$(string.MicrosoftWindows_RT_RTM)" name="MicrosoftWindows_RT_RTM" versionIndex="0" />
</majorVersion>
<majorVersion displayName="$(string.MicrosoftWindowsServer_6_3)" name="MicrosoftWindowsServer_6_3" versionIndex="10">
<minorVersion displayName="$(string.MicrosoftWindowsServer_6_3_RTM)" name="MicrosoftWindowsServer_6_3_RTM" versionIndex="0" />
</majorVersion>
<majorVersion displayName="$(string.MicrosoftWindows_6_3)" name="MicrosoftWindows_6_3" versionIndex="11">
<minorVersion displayName="$(string.MicrosoftWindows_6_3_RTM)" name="MicrosoftWindows_6_3_RTM" versionIndex="0" />
</majorVersion>
<majorVersion displayName="$(string.MicrosoftWindows_6_3_RT)" name="MicrosoftWindows_6_3_RT" versionIndex="12">
<minorVersion displayName="$(string.MicrosoftWindows_6_3_RT_RTM)" name="MicrosoftWindows_6_3_RT_RTM" versionIndex="0" />
</majorVersion>
<majorVersion displayName="$(string.MicrosoftWindowsServer_10_0)" name="MicrosoftWindowsServer_10_0" versionIndex="13">
<minorVersion displayName="$(string.MicrosoftWindowsServer_10_0_RTM)" name="MicrosoftWindowsServer_10_0_RTM" versionIndex="0" />
</majorVersion>
<majorVersion displayName="$(string.MicrosoftWindows_10_0)" name="MicrosoftWindows_10_0" versionIndex="14">
<minorVersion displayName="$(string.MicrosoftWindows_10_0_RTM)" name="MicrosoftWindows_10_0_RTM" versionIndex="0" />
</majorVersion>
<majorVersion displayName="$(string.MicrosoftWindows_10_0_RT)" name="MicrosoftWindows_10_0_RT" versionIndex="15">
<minorVersion displayName="$(string.MicrosoftWindows_10_0_RT_RTM)" name="MicrosoftWindows_10_0_RT_RTM" versionIndex="0" />
</majorVersion>
</product>
<strings><string id="Microsoft.Policies.Products:MicrosoftWindows">Windows operating system</string><string id="Microsoft.Policies.Products:MicrosoftWindows2000">Windows 2000 operating systems</string><string id="Microsoft.Policies.Products:MicrosoftWindows2000_RTM">Windows 2000</string><string id="Microsoft.Policies.Products:MicrosoftWindows2000_SP1">Windows 2000 Service Pack 1</string><string id="Microsoft.Policies.Products:MicrosoftWindows2000_SP2">Windows 2000 Service Pack 2</string><string id="Microsoft.Policies.Products:MicrosoftWindows2000_SP3">Windows 2000 Service Pack 3</string><string id="Microsoft.Policies.Products:MicrosoftWindows2000_SP4">Windows 2000 Service Pack 4</string><string id="Microsoft.Policies.Products:MicrosoftWindows7">Windows 7 operating systems</string><string id="Microsoft.Policies.Products:MicrosoftWindows7_RTM">Windows 7</string><string id="Microsoft.Policies.Products:MicrosoftWindows8">Windows 8 operating systems</string><string id="Microsoft.Policies.Products:MicrosoftWindows8_RTM">Windows 8</string><string id="Microsoft.Policies.Products:MicrosoftWindowsServer2003">Windows Server 2003 operating systems</string><string id="Microsoft.Policies.Products:MicrosoftWindowsServer2003_R2">Windows Server 2003 R2</string><string id="Microsoft.Policies.Products:MicrosoftWindowsServer2003_RTM">Windows Server 2003</string><string id="Microsoft.Policies.Products:MicrosoftWindowsServer2003_SP1">Windows Server 2003 Service Pack 1</string><string id="Microsoft.Policies.Products:MicrosoftWindowsServer2003_SP2">Windows Server 2003 Service Pack 2</string><string id="Microsoft.Policies.Products:MicrosoftWindowsServer8">Windows Server 2012 operating systems</string><string id="Microsoft.Policies.Products:MicrosoftWindowsServer8_RTM">Windows Server 2012</string><string id="Microsoft.Policies.Products:MicrosoftWindowsServer_10_0">Windows Server 2016 operating systems</string><string id="Microsoft.Policies.Products:MicrosoftWindowsServer_10_0_RTM">Windows Server 2016</string><string id="Microsoft.Policies.Products:MicrosoftWindowsServer_6_3">Windows Server 2012 R2 operating systems</string><string id="Microsoft.Policies.Products:MicrosoftWindowsServer_6_3_RTM">Windows Server 2012 R2</string><string id="Microsoft.Policies.Products:MicrosoftWindowsVista">Windows Vista operating systems</string><string id="Microsoft.Policies.Products:MicrosoftWindowsVista_RTM">Windows Vista</string><string id="Microsoft.Policies.Products:MicrosoftWindowsVista_SP1">Windows Vista Service Pack 1</string><string id="Microsoft.Policies.Products:MicrosoftWindowsXP">Windows XP operating systems</string><string id="Microsoft.Policies.Products:MicrosoftWindowsXP_RTM">Windows XP</string><string id="Microsoft.Policies.Products:MicrosoftWindowsXP_SP1">Windows XP Service Pack 1</string><string id="Microsoft.Policies.Products:MicrosoftWindowsXP_SP2">Windows XP Service Pack 2</string><string id="Microsoft.Policies.Products:MicrosoftWindows_10_0">Windows 10 operating systems</string><string id="Microsoft.Policies.Products:MicrosoftWindows_10_0_RT">Windows 10 RT operating systems</string><string id="Microsoft.Policies.Products:MicrosoftWindows_10_0_RTM">Windows 10</string><string id="Microsoft.Policies.Products:MicrosoftWindows_10_0_RT_RTM">Windows 10 RT</string><string id="Microsoft.Policies.Products:MicrosoftWindows_6_3">Windows 8.1 operating systems</string><string id="Microsoft.Policies.Products:MicrosoftWindows_6_3_RT">Windows RT 8.1 operating systems</string><string id="Microsoft.Policies.Products:MicrosoftWindows_6_3_RTM">Windows 8.1</string><string id="Microsoft.Policies.Products:MicrosoftWindows_6_3_RT_RTM">Windows RT 8.1</string><string id="Microsoft.Policies.Products:MicrosoftWindows_RT">Windows RT operating systems</string><string id="Microsoft.Policies.Products:MicrosoftWindows_RT_RTM">Windows RT</string><string id="Microsoft.Policies.Products:WindowsServer2008">Windows Server 2008 operating systems</string><string id="Microsoft.Policies.Products:WindowsServer2008_R2">Windows Server 2008 R2</string><string id="Microsoft.Policies.Products:WindowsServer2008_RTM">Windows Server 2008</string></strings>
Microsoft.Policies.Windows:category:WindowsComponents
<category displayName="$(string.WindowsComponents)" explainText="$(string.WindowsComponents_Help)" name="WindowsComponents" xmlns="http://schemas.microsoft.com/GroupPolicy/2006/07/PolicyDefinitions" />
<strings><string id="Microsoft.Policies.Windows:WindowsComponents">Windows Components</string><string id="Microsoft.Policies.Windows:WindowsComponents_Help">Contains settings for operating system components.</string></strings>
Microsoft.Policies.Windows:definition:SUPPORTED_WindowsNET
<definition displayName="$(string.SUPPORTED_WindowsNET)" name="SUPPORTED_WindowsNET" xmlns="http://schemas.microsoft.com/GroupPolicy/2006/07/PolicyDefinitions">
<or>
<range minVersionIndex="3" ref="Microsoft.Policies.Products:MicrosoftWindows" />
</or>
</definition>
<strings><string id="Microsoft.Policies.Windows:SUPPORTED_WindowsNET">At least Windows Server 2003</string></strings>