服务器日志有异常信息
Event code: 4005 
Event message: 请求的窗体身份验证失败。 原因: 提供的票证已过期。 
Event time: 2012/4/27 11:32:39 
Event time (UTC): 2012/4/27 3:32:39 
Event ID: 07a4bda5efa743e192345adf2ef032a4 
Event sequence: 6460 
Event occurrence: 111 
Event detail code: 50202 
 
Application information: 
  Application domain: /LM/W3SVC/6/ROOT-1-129799671435659885 
  Trust level: Full 
  Application Virtual Path: / 
  Application Path: E:\szxy\county1\web\ 
  Machine name: S2XYAPP2 
 
Process information: 
  Process ID: 34124 
  Process name: w3wp.exe 
  Account name: NT AUTHORITY\NETWORK SERVICE 
 
Request information: 
  Request URL: http://county1school.tyxiaoyuan.com/indexlog.aspx 
  Request path: /indexlog.aspx 
  User host address: 183.64.169.2 
  User:  
  Is authenticated: False 
  Authentication Type:  
  Thread account name: NT AUTHORITY\NETWORK SERVICE 
 
Name to authenticate:  
 
Custom event details: 
请问这是怎么回事？如何处理

------解决方案--------------------
cookie 过期 或者是 使用了相同的cookie名，cookie路径 ，machinekey