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How to alter the Kerberos time synchronization tolerance

Kerberos is a time sensitive authentication system.  This is good.  The time tolerance helps to prevent a replay attack.  You can make this tolerance more or less stricter then the default of 5 minutes.  Network packets for Kerberos authentication that have a time stamp within the tolerance value, as compared to the domain controllers clock, is considered valid.

For a local computer, you would open the local security policy.

For a domain joined computer, open a GPO that applies to the client.

For a Domain Controller, open the Default Domain Policy GPO.

Expand: Computer Configuration / Policies / Windows Settings / Security Settings / Account Policies

Open Maximum tolerance for computer clock synchronization

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Check Define this policy setting.

Enter in the number of minutes you will allow clocks to be out of sync and click OK

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