Set maximum Kerberos SSPI context token buffer size
Verified with Windows 11 25H2 — updated on July 30, 2026
Supported on: At least Windows Server 2003 operating systems or Windows XP Professional
Path in the GPO console
Computer Configuration\Administrative Templates\System\Kerberos Description
This policy setting allows you to set the value returned to applications which request the maximum size of the SSPI context token buffer size. The size of the context token buffer determines the maximum size of SSPI context tokens an application expects and allocates. Depending upon authentication request processing and group memberships, the buffer might be smaller than the actual size of the SSPI context token. If you enable this policy setting, the Kerberos client or server uses the configured value, or the locally allowed maximum value, whichever is smaller. If you disable or do not configure this policy setting, the Kerberos client or server uses the locally configured value or the default value. Note: This policy setting configures the existing MaxTokenSize registry value in HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa\Kerberos\Parameters, which was added in Windows XP and Windows Server 2003, with a default value of 12,000 bytes. Beginning with Windows 8 the default is 48,000 bytes. Due to HTTP's base64 encoding of authentication context tokens, it is not advised to set this value more than 48,000 bytes.
Registry
System\CurrentControlSet\Control\Lsa\Kerberos\Parameters Value name: EnableMaxTokenSize
Enabled: EnableMaxTokenSize = 1
Disabled: EnableMaxTokenSize = 0
MDM / Intune (CSP)
./Device/Vendor/MSFT/Policy/Config/Kerberos/SetMaximumContextTokenSize 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: Set maximum Kerberos SSPI context token buffer size
; State: Enabled
; Supported on: At least Windows Server 2003 operating systems or Windows XP Professional
[HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Lsa\Kerberos\Parameters]
"EnableMaxTokenSize"=dword:00000001
"MaxTokenSize"=dword:0000bb80More formats (PowerShell, Intune, SCCM)
PowerShell
# Exported from gporais.com
# Policy: Set maximum Kerberos SSPI context token buffer size
# State: Enabled
# Supported on: At least Windows Server 2003 operating systems or Windows XP Professional
$path = 'HKLM:\System\CurrentControlSet\Control\Lsa\Kerberos\Parameters'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'EnableMaxTokenSize' -Value 1 -Type DWord
Set-ItemProperty -Path $path -Name 'MaxTokenSize' -Value 48000 -Type DWordIntune XML
OMA-URI: ./Device/Vendor/MSFT/Policy/Config/Kerberos/SetMaximumContextTokenSize
Data type: String
Value:
<enabled/>
<data id="MaxTokenSize" value="48000"/>Intune Remediation
# === Detection script ===
# Exported from gporais.com
# Policy: Set maximum Kerberos SSPI context token buffer size
# State: Enabled
# Supported on: At least Windows Server 2003 operating systems or Windows XP Professional
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
}
$checks = @(
(Test-RegistryValue -Path 'HKLM:\System\CurrentControlSet\Control\Lsa\Kerberos\Parameters' -Name 'EnableMaxTokenSize' -Expected 1 -Kind DWord)
(Test-RegistryValue -Path 'HKLM:\System\CurrentControlSet\Control\Lsa\Kerberos\Parameters' -Name 'MaxTokenSize' -Expected 48000 -Kind DWord)
)
if ($checks -notcontains $false) {
Write-Output 'Compliant'
exit 0
}
Write-Output 'Non-compliant'
exit 1
# === Remediation script ===
# Exported from gporais.com
# Policy: Set maximum Kerberos SSPI context token buffer size
# State: Enabled
# Supported on: At least Windows Server 2003 operating systems or Windows XP Professional
$path = 'HKLM:\System\CurrentControlSet\Control\Lsa\Kerberos\Parameters'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'EnableMaxTokenSize' -Value 1 -Type DWord
Set-ItemProperty -Path $path -Name 'MaxTokenSize' -Value 48000 -Type DWordSCCM scripts
# Exported from gporais.com
# Policy: Set maximum Kerberos SSPI context token buffer size
# State: Enabled
# Supported on: At least Windows Server 2003 operating systems or Windows XP Professional
# 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: Set maximum Kerberos SSPI context token buffer size
# State: Enabled
# Supported on: At least Windows Server 2003 operating systems or Windows XP Professional
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
}
$checks = @(
(Test-RegistryValue -Path 'HKLM:\System\CurrentControlSet\Control\Lsa\Kerberos\Parameters' -Name 'EnableMaxTokenSize' -Expected 1 -Kind DWord)
(Test-RegistryValue -Path 'HKLM:\System\CurrentControlSet\Control\Lsa\Kerberos\Parameters' -Name 'MaxTokenSize' -Expected 48000 -Kind DWord)
)
if ($checks -notcontains $false) {
Write-Output 'Compliant'
exit 0
}
Write-Output 'Non-compliant'
exit 1
# === Remediation script ===
# Exported from gporais.com
# Policy: Set maximum Kerberos SSPI context token buffer size
# State: Enabled
# Supported on: At least Windows Server 2003 operating systems or Windows XP Professional
$path = 'HKLM:\System\CurrentControlSet\Control\Lsa\Kerberos\Parameters'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'EnableMaxTokenSize' -Value 1 -Type DWord
Set-ItemProperty -Path $path -Name 'MaxTokenSize' -Value 48000 -Type DWordBuilding a multi-setting collection? Add this setting and generate combined .reg / PowerShell / GPO scripts.