Audit SMB client SPN support
Verified with Windows 11 25H2 — updated on July 10, 2026
Supported on: At least Windows Server 2008 R2 or Windows 7
Path in the GPO console
Computer Configuration\Administrative Templates\Network\Lanman Server Description
This policy controls whether the SMB server audits the Service Principal Name (SPN) provided by SMB clients during authentication. If you enable this policy setting, the SMB server will log an event whenever an SMB client doesn't send SPN or sends an invalid SPN during authentication. This audit data can help identify clients that may be incompatible with SPN validation before enforcement is enabled on SMB server. If you disable or do not configure this policy setting, the SMB server will not log the event.
Registry
Software\Policies\Microsoft\Windows\LanmanServer Value name: AuditClientSpnSupport
Enabled: AuditClientSpnSupport = 1
Disabled: AuditClientSpnSupport = 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: Audit SMB client SPN support
; State: Enabled
; Supported on: At least Windows Server 2008 R2 or Windows 7
[HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Windows\LanmanServer]
"AuditClientSpnSupport"=dword:00000001 More formats (PowerShell, Intune, SCCM)
PowerShell
# Exported from gporais.com
# Policy: Audit SMB client SPN support
# State: Enabled
# Supported on: At least Windows Server 2008 R2 or Windows 7
$path = 'HKLM:\Software\Policies\Microsoft\Windows\LanmanServer'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'AuditClientSpnSupport' -Value 1 -Type DWord Intune 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: Audit SMB client SPN support
# State: Enabled
# Supported on: At least Windows Server 2008 R2 or Windows 7
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
}
$checks = @(
(Test-RegistryValue -Path 'HKLM:\Software\Policies\Microsoft\Windows\LanmanServer' -Name 'AuditClientSpnSupport' -Expected 1 -Kind DWord)
)
if ($checks -notcontains $false) {
Write-Output 'Compliant'
exit 0
}
Write-Output 'Non-compliant'
exit 1
# === Remediation script ===
# Exported from gporais.com
# Policy: Audit SMB client SPN support
# State: Enabled
# Supported on: At least Windows Server 2008 R2 or Windows 7
$path = 'HKLM:\Software\Policies\Microsoft\Windows\LanmanServer'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'AuditClientSpnSupport' -Value 1 -Type DWord SCCM scripts
# Exported from gporais.com
# Policy: Audit SMB client SPN support
# State: Enabled
# Supported on: At least Windows Server 2008 R2 or Windows 7
# 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: Audit SMB client SPN support
# State: Enabled
# Supported on: At least Windows Server 2008 R2 or Windows 7
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
}
$checks = @(
(Test-RegistryValue -Path 'HKLM:\Software\Policies\Microsoft\Windows\LanmanServer' -Name 'AuditClientSpnSupport' -Expected 1 -Kind DWord)
)
if ($checks -notcontains $false) {
Write-Output 'Compliant'
exit 0
}
Write-Output 'Non-compliant'
exit 1
# === Remediation script ===
# Exported from gporais.com
# Policy: Audit SMB client SPN support
# State: Enabled
# Supported on: At least Windows Server 2008 R2 or Windows 7
$path = 'HKLM:\Software\Policies\Microsoft\Windows\LanmanServer'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'AuditClientSpnSupport' -Value 1 -Type DWord Building a multi-setting collection? Add this setting and generate combined .reg / PowerShell / GPO scripts.