Errors trough the whole blog.

Hello, at first place thanks for reading this.

I’ve just switched from Joomla to WordPress, becaus WordPress is just what i was looking for,
A simple CMS.
But now the trouble begins.

When you enter : https://www.ravii.nl you notice there is nothing wrong.

till you go the the login page:

https://www.ravii.nl/wp-login.php

There you see there is a error :

Warning: Cannot modify header information – headers already sent by (output started at /home/raviinl/public_html/wp-config.php:24) in /home/raviinl/public_html/wp-login.php on line 9

And when i just ignore it, and try to login, i get 4 errors and nothing eals.
i checked line 9 in the file, but i couldn’t find anything wrong.
i hoped that maby you could help me.

ravii.