Quote Originally Posted by Strelizia View Post
PHP Warning: Cannot modify header information - headers already sent by (output started at /home/user/mysite.se/includes/languages/swedish/extra_definitions/mytemplate/multi_xsell_box_defines.php:1) in /home/user/mysite.se/includes/functions/functions_general.php on line 45
Take a look at this article
http://www.zen-cart.com/content.php?...s-already-sent

Remove any blank spaces / lines after the final closing ?> in your new swedish file

See if that solves your problem?