Current version will not work without this update, you will receive an expired SSL cert on checkout. To fix this you need to update the URL that it points to gotobilling.

Line 219: change

$this->form_action_url = 'https://www.paymentaccess.com/os/system/gateway/transact.php';

to

$this->form_action_url = 'https://secure.gotobilling.com/os/system/gateway/transact.php';


and you should be all set. File attached with changes below.

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