In this guide, we'll walk you through the process of fixing the "Call to Undefined Function Get_header()" issue in WordPress. This error typically occurs when the "get_header()" function is missing from a WordPress theme or plugin, causing the website to break and display an error message. By following the steps outlined in this guide, you'll be able to resolve this issue and get your site up and running again.
Table of Contents
- Understanding the 'Call to Undefined Function Get_header()' Error
- Common Causes of the Error
- Fixing the Error
- Check Your Theme's Functions.php File
- Revert to a Default Theme
- Check Your Plugins
- Update WordPress Core
- FAQs
Understanding the 'Call to Undefined Function Get_header()' Error
The "Call to Undefined Function Get_header()" error is a common WordPress issue that occurs when the "get_header()" function isn't found in the active theme or a plugin. The "get_header()" function is a crucial part of the WordPress template hierarchy and is responsible for including the header.php file in your theme.
When the function is missing, it results in a broken site and an error message similar to the following:
Fatal error: Call to undefined function get_header() in /path/to/your/website/wp-content/themes/your-theme/index.php on line XX
Common Causes of the Error
There are several reasons why the "Call to Undefined Function Get_header()" error might occur:
- A missing or corrupt functions.php file in your theme.
- An issue with a plugin that uses the "get_header()" function.
- Outdated WordPress core files.
Fixing the Error
To resolve the "Call to Undefined Function Get_header()" error, follow the steps below:
Check Your Theme's Functions.php File
The first step to troubleshoot the error is to check your theme's functions.php file. Ensure that the file exists and doesn't contain any syntax errors. You can access the file via an FTP client or your hosting's file manager.
- Navigate to the
/wp-content/themes/your-theme/directory. - Open the
functions.phpfile and ensure that it contains the following line of code:
<?php get_header(); ?>
If the code is missing, add it to the file, save your changes, and refresh your website to see if the error is resolved.
Revert to a Default Theme
If the error persists after checking the functions.php file, try reverting to a default WordPress theme like Twenty Twenty-One.
- Access your WordPress admin panel.
- Navigate to Appearance > Themes.
- Activate a default theme (e.g., Twenty Twenty-One).
- Refresh your website to see if the error is resolved.
If the error disappears, it's likely that your previous theme is causing the issue. You can either contact the theme developer for assistance or choose a different theme.
Check Your Plugins
If the error still occurs with a default theme, one or more of your plugins might be causing the issue. To troubleshoot, deactivate your plugins one by one and check your website after each deactivation.
- Access your WordPress admin panel.
- Navigate to Plugins > Installed Plugins.
- Deactivate each plugin one at a time, refreshing your website after each deactivation to see if the error is resolved.
If the error disappears after deactivating a specific plugin, contact the plugin developer for assistance or look for an alternative plugin.
Update WordPress Core
If none of the above steps resolve the error, make sure your WordPress installation is up to date.
- Access your WordPress admin panel.
- Navigate to Dashboard > Updates.
- Click the Update Now button (if available) to update WordPress to the latest version.
After updating, refresh your website to see if the error is resolved.
FAQs
Q: Can I use an FTP client to edit the functions.php file?
A: Yes, you can use an FTP client like FileZilla to access your website's files and edit the functions.php file.
Q: How do I create a backup of my theme before making any changes?
A: You can create a backup of your theme by downloading the entire theme folder from the /wp-content/themes/ directory using an FTP client or your hosting's file manager.
Q: What if I don't have access to my WordPress admin panel?
A: If you're unable to access your WordPress admin panel, you can deactivate your theme and plugins by renaming their respective folders in the /wp-content/themes/ and /wp-content/plugins/ directories using an FTP client or your hosting's file manager.
Q: Can a caching plugin cause the "Call to Undefined Function Get_header()" error?
A: Although it's rare, a caching plugin might cause the error if it's caching an outdated version of your theme or plugin files. To rule out this possibility, try clearing your cache or temporarily deactivating your caching plugin.
Q: Is there a way to prevent this error from happening in the future?
A: To prevent the "Call to Undefined Function Get_header()" error from occurring in the future, keep your WordPress installation, themes, and plugins up to date, and always create backups before making any changes to your site.