I’m also getting an error when I try to post (after having run the upgrade.php script). The error I get is as follows:
WordPress database error: [Table ‘dbname.wp_post2cat’ doesn’t exist]
SELECT cat_ID AS ID, MAX(post_modified) AS last_mod FROM wp_posts
p LEFT JOIN wp_post2cat
pc ON p.ID = pc.post_id LEFT JOIN wp_categories
c ON pc.category_id = c.cat_ID WHERE post_status = ‘publish’ GROUP BY cat_ID
I upgraded via Fantistico via my host, BlueHost.
Before I upgraded, I had no problems posting to WordPress.