Validation of viewstate MAC failed- Server Error in '/' Application

Question

I got this error when i access my hosted web application(in VS2008 C# ASP.NET 3.5 Framework)

Validation of viewstate MAC failed. If this application is ho

Answer 1

I believe that your problem is in App Pool "Idle timeout" field. You have to ask to your provider to change it to something greater... say 20mins

Take a look here.