Two problems, help me please!

Warning: Cannot modify header information – headers already sent by (output started at /home/indianzu/public_html/asieselfutbol/wp-settings.php:1) in /home/indianzu/public_html/asieselfutbol/wp-includes/classes.php on line 1571

This message appears when I want to edit one add.

My other problem is when someone wants to register on my blog, there appears a message like this.

Warning: Cannot modify header information – headers already sent by (output started at /home/indianzu/public_html/asieselfutbol/wp-settings.php:1) in /home/indianzu/public_html/asieselfutbol/wp-includes/pluggable.php on line 850

Thanks for your answer and sorry for my english, I know its so bad.