event id 40960

Windows XP event log messages Event ID 40960 Event ID 4 SPNEGO; KRB_AP_ERR_MODIFIED

A client was saying that it was taking 15 minutes in the morning to login to the computer. I found when logged onto the computer and attempted to access the domain server shares that I was being prompted for the username and password; and he was still not connecting. The event log on the workstation.