Hi,
I am experiencing the same problems and have followed all of the recommendations: I have been sure to remove any spaces before the opening <?php and after the closing ?> (btw, are all of the wp core files supposed to have a closing tag? wp-includes/pluggable.php, wp-includes/functions.php, index.php, and others didn’t…)
I have saved the files locally, opened them with TextWrangler and saved as UTF-8 without BOM, retyped the opening and closing tags, etc.
Here is the error I keep getting. And I cannot get into wp-admin so I have started deleting plugins via ftp but that’s not ideal because some may use the database…
Cannot modify header information - headers already sent by (output started at /home/XXXX/public_html/wp-includes/functions.php:2841) in /home/XXXX/public_html/wp-includes/pluggable.php on line 876
I don’t want to confuse the topic, but I also get
register_sidebar_widget is deprecated since version 2.8! Use wp_register_sidebar_widget() instead. in /home/cpasu0/public_html/wp-includes/functions.php on line 2841
which I mention only because I recently updated wordpress and I would have thought the included functions would have been updated and because the error messages reference the same line in the same file??
Is there a good source to see what should be in a wordpress install? A good way to determine which files have been corrupted? a type of version control? Thanks for any help!