Troubleshooting 101: Nasty Errors
Some of my clients have come across something similar to this nasty little error message after updating to WordPress 3.0:
Warning: call_user_func(extract_terms::update_taxonomy_count) [function.call-user-func]: First argument is expected to be a valid callback in .....wp-includes/taxonomy.php on line 2056
Warning: Cannot modify header information - headers already sent by (output started at .../wp-includes/taxonomy.php:2056) in ...../wp-includes/pluggable.php on line 890
After futzing around and asking questions about how they upgraded, I found that none of them deactivated their plugins first.
Just to refresh your memory, here are the basic steps for upgrading using WordPress’s built-in upgrade tool:
- Back up your database and your wp-contents folder
- Deactivate all your plugins
- Upgrade (plugins first, WordPress second)
- Reactivate your plugins
- Test
Reactivating your plugins one-by-one and testing (that is, reloading your site and publishing or re-publishing a post) after you activate each one is important, and time consuming. But it’s the first thing I do whenever a WordPress site is throwing scary-looking errors.
If you still have problems, and WordPress is still throwing up errors, try switching to the default theme (in WP 3.0 it’s TwentyTen), and reloading your site. Sometimes themes that haven’t been updated in a while can conflict with some code in a new update.
If you’re still having trouble with your WP 3.0 install and are this close to tossing your computer out the window, put the computer down, take a deep breath, and get in touch with me.
