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

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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With the AD Recycle Bin Turned on, What Happens when you Create a User Account with a Password that does not meet the Password Policy?

This was an interesting observation from one of my Windows Server 2012 classes. While working with the AD Recycle bin in a lab, one of my students discovered some interesting accounts that were created. When he created user accounts that did not meet password complexity requirements, an account is temporarily made and then deleted. When a new password is provided that meets the password requirements, then a new account is made. We discovered this in two places. First off in the Active Directory Administrative Center. This is what caused the initial confusion. Take a look. This is in the Deleted Objects OU. You can see multiple deleted accounts for Test2 and one for Test3. Test3 is a valid, functioning user account. Using the PowerShell command Get-ADObject –IncludeDeletedObjects –Filter * –Properties ObjectSID we can see that indeed, two accounts were created, with one of them deleted. Notice the RID portion of the SID is different. ...

How to run GPResult on a remote client with PowerShell

In the past, to run the GPResult command, you would need to either physically visit this client, have the user do it, or use and RDP connection. In all cases, this will disrupt the user. First, you need PowerShell remoting enabled on the target machine. You can do this via Group Policy . Open PowerShell and type this command. Invoke-Command –ScriptBlock {GPResult /r} –ComputerName <ComputerName> Replace <ComputerName> with the name of the target. Remember, the target needs to be online and accessible to you.

Sticky Key problem between Windows Server 2012 and LogMeIn

This week I instructed my first class using Windows Server 2012 accessed via LogMeIn and discovered a Sticky Key problem every time you press the Shift key. Here is my solution to resolve this. First off, in the Preferences of LogMeIn for the connection to the Windows Server, click General . Change the Keyboard and mouse priority to Host side user and click Apply at the bottom. On the Windows 2012 server, open the Control Panel – Ease of Access – Change how your keyboard works . Uncheck Turn on Sticky Keys . Click Set up Sticky Keys . Uncheck Turn on Sticky Keys when SHIFT is pressed five times . Click OK twice. If you are using Windows Server 2012 as a Hyper-V host, you will need to redo the Easy of Use settings on each guest operating system in order to avoid the Sticky Key Problem. Updated Information: March 20, 2013 If you continue to have problems, Uncheck Turn on Filter Keys .

Jason Yoder, MCT

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