Export to Excel issue

I have a web form that contains a GridView, which impliments Search in Grid with a TextBox and Button control in the footer. This works as I have it now. I have also implimented a Export to Excel function. The Export to Excel works by itself if the Search in Grid function is not included in the footer.
The Export to Excel function errors when trying to render the Grid for the export.  Is there a better way to incorporate both functions and accomplish the same thing? Am I missing something simple?
 
Thanks,
Here is the ASPX code;
 
<%@ Page Language="C#" MasterPageFile="~/BNSF.master" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" Title="Locked Group Status" %> <%@ Register assembly="System.Web.DynamicData, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" names ...