Mandate the maximum version of SMB
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 the maximum version of SMB protocol Note: This group policy does not prevent use of SMB 1 if that component is still installed and enabled.
Registry
HKLM
Software\Policies\Microsoft\Windows\LanmanWorkstation MDM / Intune (CSP)
./Device/Vendor/MSFT/Policy/Config/LanmanWorkstation/MaxSmb2Dialect Microsoft Learn documentation Mapping data: Microsoft Learn (CC BY 4.0)
CSP values
-
514- SMB 2.0.2. -
528- SMB 2.1.0. -
768- SMB 3.0.0. -
770- SMB 3.0.2. -
785 (Default)- SMB 3.1.1.
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: Mandate the maximum version of SMB
; State: Enabled
; Supported on: At least Windows Server 2025, Windows 11
[HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Windows\LanmanWorkstation]
"MaxSmb2Dialect"=dword:00000311More formats (PowerShell, Intune, SCCM)
PowerShell
# Exported from gporais.com
# Policy: Mandate the maximum version of SMB
# State: Enabled
# Supported on: At least Windows Server 2025, Windows 11
$path = 'HKLM:\Software\Policies\Microsoft\Windows\LanmanWorkstation'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'MaxSmb2Dialect' -Value 785 -Type DWordIntune XML
OMA-URI: ./Device/Vendor/MSFT/Policy/Config/LanmanWorkstation/MaxSmb2Dialect
Data type: String
Value:
<enabled/>
<data id="MaxSmb2Dialect" value="785"/>Intune Remediation
# === Detection script ===
# Exported from gporais.com
# Policy: Mandate the maximum version of SMB
# 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
}
$checks = @(
(Test-RegistryValue -Path 'HKLM:\Software\Policies\Microsoft\Windows\LanmanWorkstation' -Name 'MaxSmb2Dialect' -Expected 785 -Kind DWord)
)
if ($checks -notcontains $false) {
Write-Output 'Compliant'
exit 0
}
Write-Output 'Non-compliant'
exit 1
# === Remediation script ===
# Exported from gporais.com
# Policy: Mandate the maximum version of SMB
# State: Enabled
# Supported on: At least Windows Server 2025, Windows 11
$path = 'HKLM:\Software\Policies\Microsoft\Windows\LanmanWorkstation'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'MaxSmb2Dialect' -Value 785 -Type DWordSCCM scripts
# Exported from gporais.com
# Policy: Mandate the maximum version of SMB
# 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: Mandate the maximum version of SMB
# 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
}
$checks = @(
(Test-RegistryValue -Path 'HKLM:\Software\Policies\Microsoft\Windows\LanmanWorkstation' -Name 'MaxSmb2Dialect' -Expected 785 -Kind DWord)
)
if ($checks -notcontains $false) {
Write-Output 'Compliant'
exit 0
}
Write-Output 'Non-compliant'
exit 1
# === Remediation script ===
# Exported from gporais.com
# Policy: Mandate the maximum version of SMB
# State: Enabled
# Supported on: At least Windows Server 2025, Windows 11
$path = 'HKLM:\Software\Policies\Microsoft\Windows\LanmanWorkstation'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'MaxSmb2Dialect' -Value 785 -Type DWordBuilding a multi-setting collection? Add this setting and generate combined .reg / PowerShell / GPO scripts.