to troubleshoot the issue,
add the following code at line 1:
then edit the data assist update behavior and remove the redirect, and add the code after the <body> tag:
<?php if($_SERVER['REQUEST_METHOD'] == "POST") echo WA_DFP_AllUploadsDebug(); ?>
one issue i can see in the code is that you specified the upload folder as a server relative path:
that should be a document relative path instead:
post back the results of testing after making these changes and a copy of the update page in a zip archive instead of pasting the code to a text file .