A. The list of trusted domains should be updated whenever a trust relationship is terminated or created but this is not always the case.
To clear the machines cache of domains perform the following:
- Start the registry editor (regedit.exe)
- Move to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon
- Delete the DCache and DCacheUpdate values
- Close the registry editor
- Restart the computer