to troubleshoot, edit the insert page so that it no longer redirects, change:
$WA_redirectURL = "content_detail.php?ID=[Insert_ID]";
to:
$WA_redirectURL = "";
then add the following code at line 1 to turn on error reporting:
<?php
error_reporting(E_ALL);
ini_set('display_errors','on');
?>
and in the page body, add the following code to write the FILES array contents to the page and the upload debug info:
<?php if (isset($_POST["Insert"]) || isset($_POST["Insert_x"])) { ?>
<?php echo $WA_Sql; ?>
<pre>
<?php var_dump($FILES); ?>
</pre>
<?php echo WA_DFP_AllUploadsDebug(); ?>
<?php } ?>
post back the results after trying the insert again.