Enable remote mailslots
Verified with Windows 11 25H2 — updated on July 30, 2026
Supported on: At least Windows Server 2025, Windows 11
Path in the GPO console
Computer Configuration\Administrative Templates\Network\Lanman Workstation Description
This policy controls whether the SMB client will enable or disable remote mailslots over MUP. If you disable this policy setting, remote mailslots will not function over MUP, hence they will not go through the SMB client redirector. If you do not configure this policy setting, remote mailslots may be allowed through MUP.
Registry
HKLM
Software\Policies\Microsoft\Windows\NetworkProvider Value name: EnableMailslots
Enabled: EnableMailslots = 1
Disabled: EnableMailslots = 0
MDM / Intune (CSP)
./Device/Vendor/MSFT/Policy/Config/LanmanWorkstation/EnableMailslots Microsoft Learn documentation Mapping data: Microsoft Learn (CC BY 4.0)
CSP values
-
0 (Default)- Disabled. -
1- Enabled.
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: Enable remote mailslots
; State: Enabled
; Supported on: At least Windows Server 2025, Windows 11
[HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Windows\NetworkProvider]
"EnableMailslots"=dword:00000001More formats (PowerShell, Intune, SCCM)
PowerShell
# Exported from gporais.com
# Policy: Enable remote mailslots
# State: Enabled
# Supported on: At least Windows Server 2025, Windows 11
$path = 'HKLM:\Software\Policies\Microsoft\Windows\NetworkProvider'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'EnableMailslots' -Value 1 -Type DWordIntune XML
OMA-URI: ./Device/Vendor/MSFT/Policy/Config/LanmanWorkstation/EnableMailslots
Data type: String
Value:
<enabled/>Intune Remediation
# === Detection script ===
# Exported from gporais.com
# Policy: Enable remote mailslots
# State: Enabled
# Supported on: At least Windows Server 2025, Windows 11
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
}
$checks = @(
(Test-RegistryValue -Path 'HKLM:\Software\Policies\Microsoft\Windows\NetworkProvider' -Name 'EnableMailslots' -Expected 1 -Kind DWord)
)
if ($checks -notcontains $false) {
Write-Output 'Compliant'
exit 0
}
Write-Output 'Non-compliant'
exit 1
# === Remediation script ===
# Exported from gporais.com
# Policy: Enable remote mailslots
# State: Enabled
# Supported on: At least Windows Server 2025, Windows 11
$path = 'HKLM:\Software\Policies\Microsoft\Windows\NetworkProvider'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'EnableMailslots' -Value 1 -Type DWordSCCM scripts
# Exported from gporais.com
# Policy: Enable remote mailslots
# State: Enabled
# Supported on: At least Windows Server 2025, Windows 11
# 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: Enable remote mailslots
# State: Enabled
# Supported on: At least Windows Server 2025, Windows 11
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
}
$checks = @(
(Test-RegistryValue -Path 'HKLM:\Software\Policies\Microsoft\Windows\NetworkProvider' -Name 'EnableMailslots' -Expected 1 -Kind DWord)
)
if ($checks -notcontains $false) {
Write-Output 'Compliant'
exit 0
}
Write-Output 'Non-compliant'
exit 1
# === Remediation script ===
# Exported from gporais.com
# Policy: Enable remote mailslots
# State: Enabled
# Supported on: At least Windows Server 2025, Windows 11
$path = 'HKLM:\Software\Policies\Microsoft\Windows\NetworkProvider'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'EnableMailslots' -Value 1 -Type DWordBuilding a multi-setting collection? Add this setting and generate combined .reg / PowerShell / GPO scripts.