Hi,
The difference is that in the PayPal plugin, the redirect is done with that code:
<script type="text/javascript">
<!--
//Paypal does not work in an iframe... we add the target parameter if we detect we are within an iframe
function isIframe(){
try{
return window.self !== window.top;
}catch(e){
return false;
}
}
if(isIframe()){
document.getElementById('hikashop_paypal_form').target = '_blank';
}
document.getElementById('hikashop_paypal_form').submit();
//-->
</script>
while in the WorldPay Business Gateway plugin it is done with the code:
$doc = JFactory::getDocument();
$doc->addScriptDeclaration("window.hikashop.ready( function() {document.getElementById('hikashop_rbsworldpay_form').submit();});");
if you look at the _end files of the plugins in their respective folders in plugins/hikashoppayment/
So the issue is probably a javascript error on the page at the end of the checkout (caused by some 3rd party extension) which isn't there in the orders listing, and which isn't problematic for the way the redirect is done with the PayPal plugin.