使用$ _SESSION将变量从PHP传递到另一个PHP

I'm having a problem passing a variable from one PHP file to another PHP file. I'm trying to send the varialbe $insert to another PHP file that will just display it. For the life of me, I can't figure out why it won't work.

Any help would be great! Thanks.

1st PHP File (Sending $insert to $_SESSION['finalimage'])

<?php

 session_start();
 $insert = rand(5, 1500);
 $_SESSION['finalimage'] = $insert;

 header("Location: http://www.shmoggo.com/snapshot/snapshot_view.php");

 echo base64_decode($_POST["image"]);

 $final = base64_decode($_POST["image"]);


 $newpath = "uploads/" . $insert . ".jpg"; 
 file_put_contents($newpath, $final);

 ?>

2nd PHP File (Receiving $insert from $_SESSION['finalimage'])

 <?php

 session_start();
 $insert = $_SESSION['finalimage'];
 echo "Image Number = ". $insert;

 ?>

First thing to check is how your PHP installation is supporting sessions. There are two possible methods for "persisting" the session ID between requests:

1) using cookies or 2) using "URL rewriting" (ie each URL passes a sessionid value)

If you are using cookies check to see if your server is in fact sending a cookie to your browser.

If you are using url-rewriting the Location header that you are sending that re-routes the client browser to "snapshot_view.php" will need to be modified to include the session id. Like this:

$reroute = 'Location: http://www.shmoggo.com/snapshot/snapshot_view.php?PHPSESSID=' . session_id();
header($reroute);