logout code for forms

public partial class logout : System.Web.UI.Page
    {
        protected System.Web.UI.WebControls.Literal Literal1;
        protected void Page_Load(object sender, EventArgs e)
        {
            try
            {
                Literal1.Text = "<pre lang="c#">

;Logging out…";
Response.Cache.SetExpires(DateTime.UtcNow.AddMinutes(-1));
Response.Cache.SetCacheability(HttpCacheability.NoCache);
Response.Cache.SetNoStore();
}
catch { }
}


protected void Timer1_Tick(object sender, EventArgs e)
{
try
{
FormsAuthentication.SignOut();
Response.Redirect("helpdesk.aspx");
}
catch { }
}
}

protected void btnLogout_Click(object sender, EventArgs e)
       {

Session.Abandon();
Session.Clear();

Response.Redirect("main.aspx");
}