Allow Microsoft Edge to block navigations to external protocols in a sandboxed iframe
Verified with Microsoft Edge 152.0.4191.53 — updated on July 10, 2026
Supported on: Microsoft Edge version 99, Windows 7 or later
Path in the GPO console
Computer Configuration\Administrative Templates\Microsoft Edge User Configuration\Administrative Templates\Microsoft Edge Description
Microsoft Edge blocks navigations to external protocols inside a sandboxed iframe. If you enable or don't configure this policy, Microsoft Edge blocks those navigations. If you disable this policy, Microsoft Edge doesn't block those navigations. This policy can be used by administrators who need more time to update their internal website affected by this new restriction. This Enterprise policy is temporary; it's intended to be removed after Microsoft Edge version 117.
Registry
HKLM
Software\Policies\Microsoft\Edge HKCU
Software\Policies\Microsoft\Edge Value name: SandboxExternalProtocolBlocked
Enabled: SandboxExternalProtocolBlocked = 1
Disabled: SandboxExternalProtocolBlocked = 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: Allow Microsoft Edge to block navigations to external protocols in a sandboxed iframe
; State: Enabled
; Scope: Computer (HKLM)
; Supported on: Microsoft Edge version 99, Windows 7 or later
[HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Edge]
"SandboxExternalProtocolBlocked"=dword:00000001More formats (PowerShell, Intune, SCCM)
PowerShell
# Exported from gporais.com
# Policy: Allow Microsoft Edge to block navigations to external protocols in a sandboxed iframe
# State: Enabled
# Scope: Computer (HKLM)
# Supported on: Microsoft Edge version 99, Windows 7 or later
$path = 'HKLM:\Software\Policies\Microsoft\Edge'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'SandboxExternalProtocolBlocked' -Value 1 -Type DWordIntune XML
No direct Policy CSP / OMA-URI mapping for this policy. Use the Intune Remediation tab, or ingest the ADMX in Intune.Intune Remediation
# === Detection script ===
# Exported from gporais.com
# Policy: Allow Microsoft Edge to block navigations to external protocols in a sandboxed iframe
# State: Enabled
# Scope: Computer (HKLM)
# Supported on: Microsoft Edge version 99, Windows 7 or later
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
}
$checks = @(
(Test-RegistryValue -Path 'HKLM:\Software\Policies\Microsoft\Edge' -Name 'SandboxExternalProtocolBlocked' -Expected 1 -Kind DWord)
)
if ($checks -notcontains $false) {
Write-Output 'Compliant'
exit 0
}
Write-Output 'Non-compliant'
exit 1
# === Remediation script ===
# Exported from gporais.com
# Policy: Allow Microsoft Edge to block navigations to external protocols in a sandboxed iframe
# State: Enabled
# Scope: Computer (HKLM)
# Supported on: Microsoft Edge version 99, Windows 7 or later
$path = 'HKLM:\Software\Policies\Microsoft\Edge'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'SandboxExternalProtocolBlocked' -Value 1 -Type DWordSCCM scripts
# Exported from gporais.com
# Policy: Allow Microsoft Edge to block navigations to external protocols in a sandboxed iframe
# State: Enabled
# Scope: Computer (HKLM)
# Supported on: Microsoft Edge version 99, Windows 7 or later
# 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 Microsoft Edge to block navigations to external protocols in a sandboxed iframe
# State: Enabled
# Scope: Computer (HKLM)
# Supported on: Microsoft Edge version 99, Windows 7 or later
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
}
$checks = @(
(Test-RegistryValue -Path 'HKLM:\Software\Policies\Microsoft\Edge' -Name 'SandboxExternalProtocolBlocked' -Expected 1 -Kind DWord)
)
if ($checks -notcontains $false) {
Write-Output 'Compliant'
exit 0
}
Write-Output 'Non-compliant'
exit 1
# === Remediation script ===
# Exported from gporais.com
# Policy: Allow Microsoft Edge to block navigations to external protocols in a sandboxed iframe
# State: Enabled
# Scope: Computer (HKLM)
# Supported on: Microsoft Edge version 99, Windows 7 or later
$path = 'HKLM:\Software\Policies\Microsoft\Edge'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'SandboxExternalProtocolBlocked' -Value 1 -Type DWordBuilding a multi-setting collection? Add this setting and generate combined .reg / PowerShell / GPO scripts.