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Microsoft.Policies.Kerberos• Machine

Set maximum Kerberos SSPI context token buffer size

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.

Policy Details

Policy Name
MaxTokenSize
Registry Key
System\CurrentControlSet\Control\Lsa\Kerberos\Parameters
Value Name
EnableMaxTokenSize
Supported On
At least Windows Server 2003 operating systems or Windows XP Professional
OMA-URI (CSP)
Kerberos/SetMaximumContextTokenSize
OS Build Version:10.0.15063
CSP Version:5.0
Conflict Resolution:LastWrite
Allowed Editions:
EnterpriseEnterprise NProfessionalProfessional NEnterprise EvaluationEnterprise N EvaluationEducationEducation NEnterprise SEnterprise S NEnterprise S EvaluationEnterprise S N EvaluationPro Single LanguagePro ChinaPro WorkstationPro Workstation NPro For EducationPro For Education NEnterprisegEnterprisegnServerrdshIotenterpriseIotenterprisesCloudeditionnCloudeditionIotenterpriseskIotenterpriseseval
Policy State Values
Enabled: 1
Disabled: 0
Available Languages
en-us

Configuration Elements

Maximum size

Type: decimal

Default: 48000

Min: 12000
Max: 2147483647