hi all,

I have a shopping cart page which shows the details that which product user has selected with what quantity.

In this page when I click on any button like 'Continue shopping', I got an exception given below:

Exception Details: System.ArgumentException: Invalid postback or callback argument. Event validation is enabled using <pages enableEventValidation="true"/> in configuration or <%@ Page EnableEventValidation="true" %> in a page. For security purposes, this feature verifies that arguments to postback or callback events originate from the server control that originally rendered them. If the data is valid and expected, use the ClientScriptManager.RegisterForEventValidation method in order to register the postback or callback data for validation.

I do not know what means by this exception. This exception is occurred after applying Design Template in this page.

Please give a few time in this problem.