We have a total of 4 Domain Controllers in our environment. All running 2003 SP2.
On 1 DC I'm getting these KDC errors in my system event log. I rebooted the server.
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.