Problem of invoice/delivery notes's appearance

[vasia]

Hello,

I'm facing a problem relating to invoice & delivery note's appearance. Specifically, in pdf I can see only a heading on top area but in the main part of pdf there is no content. Furthermore, when I press in backend to download pdf it opens and gets displayed to browser. Is this a normal reaction?

I also compared some core files of website with another website where this function works correctly (it displays everything and when I click the pdf there it starts downloading)

These are the files which I compared:

controlers/invoice.php

views/tpl/invoice.php
views/tpl/invoice-history.php
views/tpl/invoice-items.php
views/tpl/invoice-order.php

What could be wrong?

My Joomla version is 2.5
And VM 2.6.8

p.s I also upload an attachment to display an example (the letters are on blur because the image has been edited)

[attachment cleanup by admin]