WordPress Fatal error: Call to undefined function current_theme_supports()


It’s another day and another WordPress error. You might see the following error after some type of update:

Fatal error: Call to undefined function current_theme_supports() in /home/u691482164/public_html/wp-includes/taxonomy.php on line 148

The exact cause is a little murky. The most likely cause for this is while you were updating WordPress or possibly a plugin, the files didn’t get updated correctly. Old files weren’t replaced or the update only partially completed. The good news it that to fix this error, you just need to do the update again. You’ll probably have to manually do the update. So if you were updating WordPress, make sure to update the appropriate files/folders (root, wp-admin, wp-content, wp-includes). But be careful not to delete your theme in wp-content. Definitely back-up your files before you start replacing things. That way you at least have something to go back to if you seriously mess things up.

I hope this helps someone. If you’re still having problems or need help, leave a comment and I’ll try to help. But I also recommend checking on the WordPress Support Forum – lots of super helpful and smart people. And if you already host your own WordPress instance or want to start, check out my list of Best WordPress Hosts.