Weird page when I click "Confirm Order" in cart

[marcinnn]

Hello everybody,
I have a weird problem with virtuemart order confirmation. I've searched this forum and all over the web for hours without luck.
The problem is: when I'm in cart and all fields are correctly filled I press 'Confirm Order' and then appears (in browser window!) a page (that I think) is an order confirmation e-mail that should be send to the client.
The screenshot of this page is attached.
And the confirmation e-mail is not sent to the client. And I think that I (administrator) should get an email that tells me I have new order - I don't get it.

I'm 100% sure that the page displays the output of this file:
/components/com_virtuemart/views/invoice/tmpl/mail_html_shopper.php

My page is: mninteriors.hekko.pl, username: qwerty, pass: qwerty
Site is currently offline (password is required), but it happens also when it's online.
I removed first order confirmation, but when there were 2 confirmations (on 'cart' site) – the problem was the same.
I'm using Joomla 2.5.4 and Virtuemart 2.0.6 + Virtuemart template from Template Monster.
Does anyone know what is going on?


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