Windows 2003 KDC 錯誤訊息處理

Windows 2003錯誤訊息：
Event ID: 20
The currently selected KDC certificate was once valid, but now is invalid and no suitable replacement was found.  Smartcard logon may not function correctly if this problem is not remedied.  Have the system administrator check on the state of the domain's public key infrastructure.  The chain status is in the error data.

解法：
執行 Certutil -dcinfo deleteBad 刪除錯誤的憑證。

參考：
http://support.microsoft.com/kb/939088