Internal server error on checkout

-- url of the page with the problem -- : nyt.fakur-design.dk/en/produkt/gaveartik...dobbeltkort/checkout
-- HikaShop version -- : 2.3.0
-- Joomla version -- : 3.3.3.
-- PHP version -- : 5.3
-- Browser(s) name and version -- : Chrome 36.0.1985.125
-- Error-message(debug-mod must be tuned on) -- : [Wed Aug 13 10:00:49 2014] [error] [client 89.150.106.101] PHP Notice: Undefined property: stdClass::$order_addresses_fields in /var/www/web237/web/media/com_hikashop/mail/order_creation_notification.text.php on line 78, referer: nyt.fakur-design.dk/da/produkt/gaveartik...dobbeltkort/checkout

[Wed Aug 13 10:00:49 2014] [error] [client 89.150.106.101] PHP Warning: Invalid argument supplied for foreach() in /var/www/web237/web/media/com_hikashop/mail/order_creation_notification.text.php on line 78, referer: nyt.fakur-design.dk/da/produkt/gaveartik...dobbeltkort/checkout

[Wed Aug 13 10:00:49 2014] [error] [client 89.150.106.101] malformed header from script. Bad header=/var/www/web237/dead.letter...: index.php, referer: nyt.fakur-design.dk/da/produkt/gaveartik...dobbeltkort/checkout

[Wed Aug 13 10:00:50 2014] [error] [client 89.150.106.101] File does not exist: /var/www/web237/web/favicon.ico

Hi

I'm currently working on my first HikaShop. The customer had it running on joomla 2.5, and I've upgraded it to newest version of joomla.

The original webhotel is fakur-design.dk
I've created a new webhotel named nyt.fakur-design.dk with a different provider, and moved the solution with akeeba.

All the settings from the old solution are kept.

The problem is that I get an internal server error on checkout. See the posted images.

Hello,
Firstly, did you done some changes through the code of your order "order creation notification" email or directly through the "order_creation_notification.text.php" file ?
Also, can you download the last Hikashop version through our website, install it and test it again ?
Thanks.

No, not really. I had a look at it, and searched the forum for an answer, but nothing relevant came up.

The loop that the error log complains about looks like this

	foreach($data->order_addresses_fields as $field){
		$fieldname = $field->field_namekey;
		$address =& $data->order_addresses[$data->cart->billing_address->address_id];
		$billing=str_replace('{'.$fieldname.'}',$fieldsClass->show($field,$address->$fieldname),$billing);
	}
	echo JText::_('HIKASHOP_BILLING_ADDRESS')."\n";
	echo preg_replace('#{(?:(?!}).)*}#i','',$billing)."\n\n";
}