Specify maximum log file size
Verified with Windows 11 25H2 — updated on July 30, 2026
Supported on: At least Windows Server 2003
Path in the GPO console
Computer Configuration\Administrative Templates\System\Net Logon Description
This policy setting specifies the maximum size in bytes of the log file netlogon.log in the directory %windir%\debug when logging is enabled. By default, the maximum size of the log file is 20MB. If you enable this policy setting, the maximum size of the log file is set to the specified size. Once this size is reached the log file is saved to netlogon.bak and netlogon.log is truncated. A reasonable value based on available storage should be specified. If you disable or do not configure this policy setting, the default behavior occurs as indicated above.
Registry
HKLM
Software\Policies\Microsoft\Netlogon\Parameters MDM / Intune (CSP)
./Device/Vendor/MSFT/Policy/Config/ADMX_Netlogon/Netlogon_MaximumLogFileSize 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: Specify maximum log file size
; State: Enabled
; Supported on: At least Windows Server 2003
[HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Netlogon\Parameters]
"MaximumLogFileSize"=dword:2000ffffMore formats (PowerShell, Intune, SCCM)
PowerShell
# Exported from gporais.com
# Policy: Specify maximum log file size
# State: Enabled
# Supported on: At least Windows Server 2003
$path = 'HKLM:\Software\Policies\Microsoft\Netlogon\Parameters'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'MaximumLogFileSize' -Value 536936447 -Type DWordIntune XML
OMA-URI: ./Device/Vendor/MSFT/Policy/Config/ADMX_Netlogon/Netlogon_MaximumLogFileSize
Data type: String
Value:
<enabled/>
<data id="Netlogon_MaximumLogFileSizeLabel" value="536936447"/>Intune Remediation
# === Detection script ===
# Exported from gporais.com
# Policy: Specify maximum log file size
# State: Enabled
# Supported on: At least Windows Server 2003
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
}
$checks = @(
(Test-RegistryValue -Path 'HKLM:\Software\Policies\Microsoft\Netlogon\Parameters' -Name 'MaximumLogFileSize' -Expected 536936447 -Kind DWord)
)
if ($checks -notcontains $false) {
Write-Output 'Compliant'
exit 0
}
Write-Output 'Non-compliant'
exit 1
# === Remediation script ===
# Exported from gporais.com
# Policy: Specify maximum log file size
# State: Enabled
# Supported on: At least Windows Server 2003
$path = 'HKLM:\Software\Policies\Microsoft\Netlogon\Parameters'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'MaximumLogFileSize' -Value 536936447 -Type DWordSCCM scripts
# Exported from gporais.com
# Policy: Specify maximum log file size
# State: Enabled
# Supported on: At least Windows Server 2003
# 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: Specify maximum log file size
# State: Enabled
# Supported on: At least Windows Server 2003
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
}
$checks = @(
(Test-RegistryValue -Path 'HKLM:\Software\Policies\Microsoft\Netlogon\Parameters' -Name 'MaximumLogFileSize' -Expected 536936447 -Kind DWord)
)
if ($checks -notcontains $false) {
Write-Output 'Compliant'
exit 0
}
Write-Output 'Non-compliant'
exit 1
# === Remediation script ===
# Exported from gporais.com
# Policy: Specify maximum log file size
# State: Enabled
# Supported on: At least Windows Server 2003
$path = 'HKLM:\Software\Policies\Microsoft\Netlogon\Parameters'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'MaximumLogFileSize' -Value 536936447 -Type DWordBuilding a multi-setting collection? Add this setting and generate combined .reg / PowerShell / GPO scripts.