Duplicate orders in 1.5.3

[delia]

I promised I would ask because I don't see how this is possible. A recently upgraded cart (from 1.3.9) is experiencing duplicate orders. Payment method is paypalpro.

I did find one line in tpl_checkout_payment_default.php that is not supposed to be there and have removed it but I don't see how that could create the situation where the buyer found it necessary to hit the submit button again:

if ($_SESSION['cart']->show_total() == 0) {
     zen_redirect(zen_href_link(FILENAME_CHECKOUT_CONFIRMATION, '', 'SSL'));
 } 

I just don't see anything else. Any ideas?

[bislewl]

Are you using the stock checkout system or something else?

[mc12345678]

The broadest question to ask might be in what ways is the code on the server different than the code of a fresh install of the same version of ZC (whether it is 1.5.4 or 1.5.3). I'm leaning towards the possibility that one of the includes/modules/pages folders has extra files in it ending with .php.

So this "duplicate" orders situation, what is the "effect"? Charged twice? Two unique new order numbers? Same order number but email sent out twice? Etc... The detailed observed action would help identify where it could be as well as where it is not (likely) to be in the processing of the order(s)? Does it happen on every order? Every order using just that payment processor? Default template? Etc...

[delia]

stock by attributes - yes.

New up to three separate orders. Customer noticed nothing out of the ordinary. Don't know whether it sent more than one email. Orders happen from 8 seconds to 1 minute apart.

[bruce429]

Just seen this happen on a recently upgraded zc 1.5.4.
3 orders, different order numbers, same paypal ID.
There was only one item to sell. The quantity on hand became -2.

[mc12345678]

Just seen this happen on a recently upgraded zc 1.5.4.
3 orders, different order numbers, same paypal ID.
There was only one item to sell. The quantity on hand became -2.

To try to help identify issue, is SBA installed on that system as well?