<form name="PrePage" method = "post" action = "https://Simplecheckout.authorize.net/payment/CatalogPayment.aspx"> <input type = "hidden" name = "LinkId" value ="2faaf1d4-ab5e-4c07-8f28-d226925f065e" /> <input type = "submit" value = "Pay Patient Balance" />< /form>