Errore PHP Notice

Salve.
Stamani dopo aver aggiornato l'index in gestione file, mi appare il seguente errore sopra il banner del forum.

[phpBB Debug] PHP Notice: in file /includes/functions.php on line 4556: Cannot modify header information - headers already sent by (output started at /index.php:64)
[phpBB Debug] PHP Notice: in file /includes/functions.php on line 4558: Cannot modify header information - headers already sent by (output started at /index.php:64)
[phpBB Debug] PHP Notice: in file /includes/functions.php on line 4559: Cannot modify header information - headers already sent by (output started at /index.php:64)
[phpBB Debug] PHP Notice: in file /includes/functions.php on line 4560: Cannot modify header information - headers already sent by (output started at /index.php:64)

http://img29.imageshack.us/img29/1043/yi4q.th.jpg

Qualcuno sapprebbe spiegarmi che errore mi sta dando e come fare per rimuoverlo?
Grazie in anticipo a tutti quelli che mi risponderanno :=):

Ho risolto ^^