关于machine.config 中配置相导致的 invalid viewstate 问题

今天又客户说访问网站是报错，发回的信息如下
System.Web.HttpException: Invalid_Viewstate
  
of viewstate failed.  1) If this is a cluster, edit configuration so all
servers use the same validationKey and validation algorithm.  AutoGenerate
cannot be used in a cluster.  2) Viewstate can only be posted back to the
same page.  3) The viewstate for this page might be corrupted. --->
System.Web.HttpException: Unable to validate data.
   at System.Web.Configuration.MachineKey.GetDecodedData(Byte[] buf, Byte[]
modifier, Int32 start, Int32 length, Int32& dataLength)
   at System.Web.UI.LosFormatter.Deserialize(String input)
   --- End of inner exception stack trace ---
   at System.Web.UI.LosFormatter.Deserialize(String input)
   at System.Web.UI.Page.LoadPageStateFromPersistenceMedium()
   --- End of inner exception stack trace ---
   at System.Web.UI.Page.LoadPageStateFromPersistenceMedium()
   at System.Web.UI.Page.LoadPageViewState()
   at System.Web.UI.Page.ProcessRequestMain()


搜索了许多信息，判断可能是因为群集的问题，根据得到的信息，修改machine.config，将 validationKey 的 AutoGenerate 去掉，给为自定义的 Value