Hi,
That problem has been fixed already but probably the PureMArt version you are holding is lack of this patch.
The solution is pretty easy though.
First find this PHP file:
ROOT/components/com_virtuemart/views/askquestion/tmpl/mail_confirmed.php
And copy this file to here:
ROOT/templates/<yourjoomlatemplate>/html/com_virtuemart/askquestion/mail_confirmed.php
then open it, and find this LINE:
<button on-click="parent.jQuery.facebox.close();" type="button"><?php echo JText::_('COM_VIRTUEMART_CLOSE'); ?></button>
And change it with this:
<button on-click="parent.jQuery.facebox.close();history.go(-1);" type="button" formaction="">
<?php echo JText::sprintf('COM_VIRTUEMART_CATEGORY_BACK_TO', $this->product->product_name); ?>
</button>
Than that button will be working properly and return to product page.
Regards.
Forum Support.