To fix the trust relationship failed error there is a quick solution that need few steps and avoid rejoining the machine to the domain.
When you login to the system you receive the error:
The trust relationship between this workstation and the primary domain failed.
The problem is due to the secure communication between the workstation and the Active Directory domain no longer working. The computer’s "private secret" doesn’t have same value stored in the Domain Controller therefore the communication handled by Kerberos cannot be established.
This situation often happen when you restore the virtual machines that use a snapshot taken months before.
You login the workstation entering the domain account and its password.
The system deny the access replying with the error message shown.
To fix Windows issues there are usually different solutions, one official fix from Microsoft and alternatives by some Administrators that can solve this matter faster.
To fix this issue, Microsoft suggest to rejoin the domain to restore the trust relationship as reported in the support article: http://support.microsoft.com/kb/162797.
The quick fix
Log as Local Administrator in the server with the problem and open the Command Prompt.
You need to locate the netdom utility that in Windows 2008 and Windows 2008 R2 is stored in the \Windows\System32 directory.
Using the utility netdom, type the following command:
netdom.exe resetpwd /s:<domaincontroller> /ud:DOMAIN\<administrator> /pd:*
C:\Windows\System32>netdom.exe resetpwd /s:w2k8r2-dc01 /ud:NOLABNOPARTY\Administrator /pd:*
If you try to login the system again, you no longer receive the error message.
Netdom.exe in Windows 7
Since Windows 7 doesn't have netdom.exe utility installed by default, you can download netdom from here.
- Copy netdom.exe in C:\Windows\System32 and netdom.exe.mui in C:\Windows\System32\en-US.
- Follow same procedure.
This solution allows you to restore the machine functionality faster with just few click without rejoining the workstation to the domain.