Generate Excel and then redirect to another page

[Guillermo D. Polonsky]

Hi, i'm exporting gridview data to excel file, and after that (after
the save as dialog pops up on client machine) i need the page to be
redirected to home page. Tha problem it's that the export rutine ends
with response.end, and anything else after that it's ignored, and if i
put the redirect command in the finally it says that http headers had
already been sent to the client, so that's not working eather. Ideas?
This is my code.

protected void Page_Load(object sender, EventArgs e)
{
Session["endWait"] = "SI";
long id = 0;

CERTIFICADO oCertificado = new CERTIFICADO();
DataTable dt;

try
{
string s =
System.Globalization.CultureInfo.CurrentCulture.DateTimeFormat.ShortDatePattern;
DateTime fecha =
System.DateTime.Parse(Request["FechaVencimiento"].ToString(),
System.Globalization.CultureInfo.CurrentCulture.DateTimeFormat);
dt = oCertificado.GenerarCertificados(Request["Letra"],
Request["Cantidad"], oCertificado.GetSerie(),
Request["FechaVencimiento"], Session["id_usuario"].ToString(), ref id);

Response.Clear();
Response.AddHeader("content-disposition",
"attachment;filename=Certificados" +
System.DateTime.Today.ToString(s).Replace('/', '-') + "-" +
System.DateTime.Now.Hour + "_" + System.DateTime.Now.Minute + "_" +
System.DateTime.Now.Second + ".xls");

Response.ContentType = "application/vnd.xls";

StringWriter sw = new StringWriter();
HtmlTextWriter htw = new HtmlTextWriter(sw);
CERTIFICADO c = new CERTIFICADO();
GridView1.DataSource = dt;
GridView1.DataBind();
GridView1.RenderControl(htw);
Response.Write(sw.ToString());
Response.End();
}
catch (Exception ex)
{
ExceptionManager.Publish(ex);
}
finally
{
oCertificado = null;
}
}

public override void VerifyRenderingInServerForm(Control control)
{
}