Untrusted Font Blocking
Verified with Windows 11 25H2 — updated on July 30, 2026
Supported on: At least Windows Server 2016, Windows 10
Path in the GPO console
Computer Configuration\Administrative Templates\System\Mitigation Options Description
This security feature provides a global setting to prevent programs from loading untrusted fonts. Untrusted fonts are any font installed outside of the %windir%\Fonts directory. This feature can be configured to be in 3 modes: On, Off, and Audit. By default, it is Off and no fonts are blocked. If you aren't quite ready to deploy this feature into your organization, you can run it in Audit mode to see if blocking untrusted fonts causes any usability or compatibility issues.
Registry
HKLM
SOFTWARE\Policies\Microsoft\Windows NT\MitigationOptions MDM / Intune (CSP)
./Device/Vendor/MSFT/Policy/Config/ADMX_GroupPolicy/FontMitigation 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: Untrusted Font Blocking
; State: Enabled
; Supported on: At least Windows Server 2016, Windows 10
[HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows NT\MitigationOptions]
"MitigationOptions_FontBocking"="1000000000000"More formats (PowerShell, Intune, SCCM)
PowerShell
# Exported from gporais.com
# Policy: Untrusted Font Blocking
# State: Enabled
# Supported on: At least Windows Server 2016, Windows 10
$path = 'HKLM:\SOFTWARE\Policies\Microsoft\Windows NT\MitigationOptions'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'MitigationOptions_FontBocking' -Value '1000000000000' -Type StringIntune XML
OMA-URI: ./Device/Vendor/MSFT/Policy/Config/ADMX_GroupPolicy/FontMitigation
Data type: String
Value:
<enabled/>
<data id="FontMitigation_DL" value="1000000000000"/>Intune Remediation
# === Detection script ===
# Exported from gporais.com
# Policy: Untrusted Font Blocking
# State: Enabled
# Supported on: At least Windows Server 2016, Windows 10
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
}
$checks = @(
(Test-RegistryValue -Path 'HKLM:\SOFTWARE\Policies\Microsoft\Windows NT\MitigationOptions' -Name 'MitigationOptions_FontBocking' -Expected '1000000000000' -Kind String)
)
if ($checks -notcontains $false) {
Write-Output 'Compliant'
exit 0
}
Write-Output 'Non-compliant'
exit 1
# === Remediation script ===
# Exported from gporais.com
# Policy: Untrusted Font Blocking
# State: Enabled
# Supported on: At least Windows Server 2016, Windows 10
$path = 'HKLM:\SOFTWARE\Policies\Microsoft\Windows NT\MitigationOptions'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'MitigationOptions_FontBocking' -Value '1000000000000' -Type StringSCCM scripts
# Exported from gporais.com
# Policy: Untrusted Font Blocking
# State: Enabled
# Supported on: At least Windows Server 2016, Windows 10
# 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: Untrusted Font Blocking
# State: Enabled
# Supported on: At least Windows Server 2016, Windows 10
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
}
$checks = @(
(Test-RegistryValue -Path 'HKLM:\SOFTWARE\Policies\Microsoft\Windows NT\MitigationOptions' -Name 'MitigationOptions_FontBocking' -Expected '1000000000000' -Kind String)
)
if ($checks -notcontains $false) {
Write-Output 'Compliant'
exit 0
}
Write-Output 'Non-compliant'
exit 1
# === Remediation script ===
# Exported from gporais.com
# Policy: Untrusted Font Blocking
# State: Enabled
# Supported on: At least Windows Server 2016, Windows 10
$path = 'HKLM:\SOFTWARE\Policies\Microsoft\Windows NT\MitigationOptions'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'MitigationOptions_FontBocking' -Value '1000000000000' -Type StringBuilding a multi-setting collection? Add this setting and generate combined .reg / PowerShell / GPO scripts.