Hi, We are getting below error on one of my windows server 2003. how to reslove. URL: >> >> http://abc.xyz.com/pqr/mno.aspx?s=188 >> >> >> >> User Agent: >> >> Mozilla/5.0 (Macintosh; Intel Mac OS X 10.5; rv:5.0.1) Gecko/20100101 >> Firefox/5.0.1 >> >> >> >> Exception Message: >> >> Validation of viewstate MAC failed. If this application is hosted by >> a Web Farm or cluster, ensure that <machineKey> configuration >> specifies the same validationKey and validation algorithm. >> AutoGenerate cannot be used in a cluster. >> >> >> >> Stack Trace: >> >> at System.Web.UI.ViewStateException.ThrowError(Exception inner, >> String persistedState, String errorPageMessage, Boolean >> macValidationError) >> >> at System.Web.UI.ObjectStateFormatter.Deserialize(String >> inputString) >> >> at System.Web.UI.Util.DeserializeWithAssert(IStateFormatter >> formatter, String serializedState) >> >> at System.Web.UI.HiddenFieldPageStatePersister.Load() >> >> at System.Web.UI.Page.LoadPageStateFromPersistenceMedium() >> >> at System.Web.UI.Page.LoadAllState() >> >> at System.Web.UI.Page.ProcessRequestMain(Boolean >> includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) >> >> at System.Web.UI.Page.ProcessRequest(Boolean >> includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) >> >> at System.Web.UI.Page.ProcessRequest() >> >> at System.Web.UI.Page.ProcessRequest(HttpContext context) >> >> at ASP.admin_manageforums_aspx.ProcessRequest(HttpContext context) >> >> at >> System.Web.HttpApplication.CallHandlerExecutionStep.System.Web.HttpAp >> p >> lication.IExecutionStep.Execute() >> >> at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, >> Boolean& >> completedSynchronously)

Vijay, I would suggest that you will recieve a much more in depth response in the iis forums. http://forums.iis.net/ this on the surface appears to be a .net configuration error for your website. -- :P Advice offered, If you need more help it is advised to seek the council and advice of paid professionals. The answer is always 42, or reboot.