The error below is showing up at the top of the screens on my site after upgrading from 2.2 to 2.3RC1 today. I tried running the upgrade script again but it wouldn't let me, saying the database is already up-to-date. Hmmm.
WordPress database error: [Table 'jeannie_wordpress.wp_categories' doesn't exist]
SELECT * FROM wp_categories ORDER BY cat_name
You can see that the categories do show up (www.jeanniebeannie.com), but the error message.
Please forgive me if this has already been covered, I didn't see anything about it in the forums.
I also get the one below sometimes (like just now when I switched the theme in order to make the previous error msg visible since it was hidden by the other theme).
Warning: Cannot modify header information - headers already sent by (output started at /home/jeannie/public_html/wordpress/wp-includes/wp-db.php:160) in /home/jeannie/public_html/wordpress/wp-includes/pluggable.php on line 383
Thanks,
Jeannie