To troubleshoot, add the following code at line 1:
<?php
error_reporting(E_ALL);
ini_set('display_errors','on');
?>
and add this code in the page body to write the file upload debug info to the page:
<?php echo WA_DFP_AllUploadsDebug(); ?>
<?php
if(isset($_FILES)) {
echo("<pre>");
var_dump($_FILES);
echo("</pre>");
}
?>
Post back the debug info that is written to the page and any errors after trying to upload again.