Yes! :lol: :lol: I found the problem. I made with sh404sef a 301-Redirect (URL-Alias) for aktione.ch/index.php, because i thoght of duplicate content. But if /index.php is redirectet to the base URL, the comment function of k2 isn't working anymore. Now it works as before. But thank you anyway for your help. I'm realy happy now :silly: