Question

I have got a button field in my grid view. When I click multiple times on the grid (3 times), I am getting an error which is shown below. The same issue is arised when I click multiple times on a page number(which is not the active page) of the grid.

Invalid postback or callback argument. Event validation is enabled
using 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.

Please help me solve the issue.

Answer 1

I guess you have added databinding code in page load without enclosing IsPostBack block.

void page_load()
{
  if(!IsPostBack) 
   {
    //put databinding code here
    }
}

EDIT:

Please read these threads/posts:

1. Invalid postback or callback argument. Event validation is enabled using ”

2. MSDN blog – Validation of viewstate MAC failed error

3. Validation of viewstate MAC failed

4. Validation of viewstate MAC failed error