Invalid postback or callback argument error?

Question

I have two dropdownlists and I am filling one based on the other using javascript. In my javascript code I am calling for a webservice and with the results returned I fill t

Answer 1

My problem was solved when cancel event at end of grid event at server side.

protected void grdEducation_RowEditing(object sender, GridViewEditEventArgs e)
{
  // do your processing ... 

  // at end     
  e.Cancel = true;
}