Don't understand error message.

Question

Update: I'm looking for any ideas on this. I know it's hard without the full script. I'm more than happy to send it to you, but it is over 450 lines. All of the database functions work fine, as does an earlier version of this script from which there are only small changes to this version. I have searched through the the changes for several days.
I'm getting the following error message on a script that I briefly changed from one that worked fine. All the database manipulations work fine. This exists only on my computer right now. The messages are:
Warning: session_start() [function.session-start]: Cannot send session cookie - headers already sent by (output started at C:\xampp\htdocs\lorianorg01\ssregister\ss07-finalregis.php:4) in C:\xampp\htdocs\lorianorg01\ssregister\ss07-finalregis.php on line 76
Warning: session_start() [function.session-start]: Cannot send session cache limiter - headers already sent (output started at C:\xampp\htdocs\lorianorg01\ssregister\ss07-finalregis.php:4) in C:\xampp\htdocs\lorianorg01\ssregister\ss07-finalregis.php on line 76
Here is the code, beginning at line 75:
//Establish session variables
session_start();
$_SESSION['ss_id'] = $regis_ss_id;
$_SESSION['ss_name'] = $regis_ss_name;
$_SESSION['ss_nomonths'] = $regis_ss_nomonths;
$_SESSION['ss_cost'] = $regis_ss_cost;
$_SESSION['ss_homelink'] = $regis_ss_link;
$_SESSION['email_address'] = $regis_email_address;
$_SESSION['first_name'] = $regis_first_name;
$_SESSION['last_name'] = $regis_last_name;

Answer 1

Thanks for the reply!
What follows is first 135 lines of code.  As I mentioned, this code in another script, works fine. I copied that code and pasted it into a new folder. I have made sure the links are still good and the database manipulations are all good using a new table. I believe that the problem is in the combination of copying the code and the changes I made. I have done a compare of the original and the changed scripts and studied it for hours to see if I can find an error. I've also put the code in Aptana to see if it picks anything up. Nothing.
<?php  require_once('../Connections/classlist.php'); ?>
<?php require_once('../Connections/ssrecords.php'); ?>
<?php
// [07] This script finalizes the registration and produces letters to Lorian and the registrant.
//The above connections provide links to the LorianSchool database for classlist and ssrecords.
//This function, generated by Dreamweaver, determines the type of information being retrieved from the database.
if (!function_exists("GetSQLValueString")) {
function GetSQLValueString($theValue, $theType, $theDefinedValue = "", $theNotDefinedValue = "")
  $theValue = get_magic_quotes_gpc() ? stripslashes($theValue) : $theValue;
  $theValue = function_exists("mysql_real_escape_string") ? mysql_real_escape_string($theValue) : mysql_escape_string($theValue);
  switch ($theType) {
    case "text":
      $theValue = ($theValue != "") ? "'" . $theValue . "'" : "NULL";
      break;   
    case "long":
    case "int":
      $theValue = ($theValue != "") ? intval($theValue) : "NULL";
      break;
    case "double":
      $theValue = ($theValue != "") ? "'" . doubleval($theValue) . "'" : "NULL";
      break;
    case "date":
      $theValue = ($theValue != "") ? "'" . $theValue . "'" : "NULL";
      break;
    case "defined":
      $theValue = ($theValue != "") ? $theDefinedValue : $theNotDefinedValue;
      break;
  return $theValue;
?>
<?php
//Pick up the "record ID" (SS ID)
$colname_DetailRS1 = "-1";
if (isset($_GET['recordID'])) {
  $colname_DetailRS1 = $_GET['recordID'];
//Get SS info from ssrecords table
mysql_select_db($database_classlist, $classlist);
$query_DetailRS1 = sprintf("SELECT * FROM ssrecords WHERE ssrecords.ss_id = %s", GetSQLValueString($colname_DetailRS1, "text"));
$DetailRS1 = mysql_query($query_DetailRS1, $classlist) or die(mysql_error());
$row_DetailRS1 = mysql_fetch_assoc($DetailRS1);
$totalRows_DetailRS1 = mysql_num_rows($DetailRS1);
$regis_ss_id = $row_DetailRS1['ss_id'];
$regis_ss_name = $row_DetailRS1['ss_name'];
$regis_ss_nomonths = $row_DetailRS1['ss_nomonths'];
$regis_ss_cost = $row_DetailRS1['ss_cost'];
$regis_ss_link = $row_DetailRS1['ss_homelink'];
// Pick up the email address
$colname_classentry = "-1";
if (isset($_GET['email_address'])) {
  $colname_classentry = $_GET['email_address'];
//Get the registrant information from the nameregistration table
mysql_select_db($database_classlist, $classlist);
$query_classentry = sprintf("SELECT * FROM nameregistration WHERE nameregistration.email_address = %s", GetSQLValueString($colname_classentry, "text"));
$classentry = mysql_query($query_classentry, $classlist) or die(mysql_error());
$row_classentry = mysql_fetch_assoc($classentry);
$totalRows_classentry = mysql_num_rows($classentry);
$regis_email_address = $row_classentry['email_address'];
$regis_first_name = $row_classentry['first_name'];
$regis_last_name = $row_classentry['last_name'];
//Establish session variables
session_start();
$_SESSION['ss_id'] = $regis_ss_id;
$_SESSION['ss_name'] = $regis_ss_name;
$_SESSION['ss_nomonths'] = $regis_ss_nomonths;
$_SESSION['ss_cost'] = $regis_ss_cost;
$_SESSION['ss_homelink'] = $regis_ss_link;
$_SESSION['email_address'] = $regis_email_address;
$_SESSION['first_name'] = $regis_first_name;
$_SESSION['last_name'] = $regis_last_name;
//Prepare to write the class registration record in SSregis table
mysql_select_db($database_ssrecords, $ssrecords);
$query_registration = "SELECT * FROM ssregis";
$registration = mysql_query($query_registration, $ssrecords) or die(mysql_error());
$row_registration = mysql_fetch_assoc($registration);
$totalRows_registration = mysql_num_rows($registration);
$editFormAction = $_SERVER['PHP_SELF'];
if (isset($_SERVER['QUERY_STRING'])) {
  $editFormAction .= "?" . htmlentities($_SERVER['QUERY_STRING']);
//On clicking Submit, insert a new record in the ssregis table   
if ((isset($_POST["MM_insert"])) && ($_POST["MM_insert"] == "form1")) {
  $regis_paid_code = $_POST["submit"];
  $insertSQL = sprintf("INSERT INTO ssregis (email_address, ss_id, ss_cost, reg_date, paid_code) VALUES (%s, %s, %s, %s, %s)",
        GetSQLValueString($regis_email_address, "text"),
                       GetSQLValueString($regis_ss_id, "text"),
                       GetSQLValueString($regis_ss_cost, "double"),
        GetSQLValueString($regis_reg_date, "date"),
        GetSQLValueString($regis_paid_code, "text"));                   
  mysql_select_db($database_ssrecords, $ssrecords);
  $Result1 = mysql_query($insertSQL, $ssrecords) or die(mysql_error());
  $regis_regid = mysql_insert_id();
  //Get ID of registration record just written in ssregis
  mysql_select_db($database_ssrecords, $ssrecords);
  $query_registration = "SELECT * FROM ssregis WHERE reg_id = '$regis_regid'";
  $registration = mysql_query($query_registration, $classlist) or die(mysql_error());
  $new_row = mysql_fetch_assoc($registration);
  //If using PayPal go to Paypalregis.php
  if ($regis_paid_code == "PayPal")  {
  $insertGoTo = "\ssregister\ss08-ppregis.php";
  if (isset($_SERVER['QUERY_STRING'])) {
    $insertGoTo .= (strpos($insertGoTo, '?')) ? "&" : "?";
    $insertGoTo .= $_SERVER['QUERY_STRING'];
$insertGoTo .= "&reg_id=".$new_row['reg_id'];
  else  {
  //If not using PayPal go to Lorian Home page.
  $insertGoTo = "lorianorg01/index.html";
  if (isset($_SERVER['QUERY_STRING'])) {
    $insertGoTo .= (strpos($insertGoTo, '?')) ? "&" : "?";
    $insertGoTo .= $_SERVER['QUERY_STRING'];
$insertGoTo .= "&reg_id=".$new_row['reg_id'];
header(sprintf("Location: %s", $insertGoTo));