King Computer Solutions
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07.29.2012

The trust relationship between this workstation and the primary domain failed

After restoring a server virtual machine to a few days prior I encountered this error. Previously I would delete the computer from the domain and rejoin it, but found a faster way.

The underlying problem when you see this error is that the machine you are trying to access can no longer communicate securely with the Active Directory domain to which it is joined. The machine’s private secret is not set to the same value store in the domain controller. You can think of this secret as a password but really it’s some bits of cryptographic data called a Kerberos keytab stored in the local security authority. When you try to access this machine using a domain account, it fails to verify the Kerberos ticket you receive from Active Directory against the private secret that it stores locally. I think you can also come across this error if for some reason the system time on the machine is out of sync with the system time on the domain controller. Resetting the computer password on the domain controller fixes this. This problem can be caused by various circumstances, but I most commonly run into it when I reset a virtual machine to a system snapshot made previously. I restored a server from only a few days before and had the problem. When the machine is reset, it is missing all of the automatic password changes that it executed against the domain controller during the intervening months. The password changes are required to maintain the security integrity of the domain.

Change your computer password using netdom.exe using the following from an elevated command prompt

netdom.exe resetpwd /s:<server> /ud:<user> /pd:*

<server> = a domain controller in the joined domain

<user> = DOMAIN\User format with rights to change the computer password

Here are the full steps:

  • You need to be able to get onto the machine. I normally just log in with the local Administrator account by typing, “.\Administrator” in the logon window. I hope you remember the password. If you’re creative and resourceful you can hack your way in without the password. Another option is to unplug the machine from the network and log in with domain user. You will be able to do disconnected authentication, but in the case of a reset machine, remember that you may have to use an old password. Your domain user’s cached credential has the same problem as the machine’s private secret.
  • You need to make sure you have netdom.exe. Where you get netdom.exe depends on what version of Windows you’re running. Windows Server 2008 and Windows Server 2008 R2 ship with netdom.exe you just have to enable the Active Directory Domain Services role. On Windows Vista and Windows 7 you can get it from the Remote Server Administration Tools (RSAT). Google can help you get them. For other platforms see this link: http://technet.microsoft.com/en-us/library/ee649281(WS.10).aspx”
  • Extra steps if the machine is a domain controller. If the broken machine is a domain controller it is a little bit more complicated, but still possible to fix the problem.
    • Turn off the Kerberos Key Distribution Center service. You can do this in the Services MMC snap-in. Set the startup type to Manual. Reboot.
    • Remove the Kerberos ticket cache. A reboot will do this for you, or you can remove them using KerbTray.exe. You can get that tool here: http://www.microsoft.com/download/en/details.aspx?displaylang=en&id=17657
    • Post change steps. Do these in conjunction with 5 below. Turn the Kerberos Key Distribution Center Service back on before rebooting. You should reboot the domain controller and then force replication in the Active Directory Sites and Services MMC snap-in.
      Run netdom.exe to change the password.
    • Open an administrative command prompt. On Windows platforms with UAC enabled, you will need to right-click on cmd.exe and select “run as Administrator”.
    • Type the following command: netdom.exe resetpwd /s:<server> /ud:<user> /pd:*
    • Reboot the machine.
  • Here is more information on netdom.exe: http://support.microsoft.com/kb/325850