How to Fix WordPress Error: “Warning: Undefined Array Key 0 in /home/…/public_html/wp-includes/meta.php on Line 638”
If you’ve recently updated the All in One SEO plugin on your WordPress website and encountered the error “Warning: Undefined array key 0 in /home/…/public_html/wp-includes/meta.php on line 638,” you’re not alone. This error can be alarming as it appears on the top of your homepage, disrupting the user experience. Here’s a detailed guide on how to resolve this issue based on a real-world scenario.
Understanding the Issue
After updating the All in One SEO plugin to version 4.7.1.1, this warning error appeared, indicating that the updated plugin might have compatibility issues with the current theme or WordPress version, leading to an undefined array key error. This is a common issue that can arise when plugins or themes update and change the way they interact with WordPress core files.
Steps to Fix the Error
Option 1: Downgrade the All in One SEO Plugin
Since the issue was caused by the latest update of the All in One SEO plugin, downgrading to a previous, stable version can be an immediate fix. Here’s how to do it:
- Download the Previous Plugin Version:
- If you have multiple websites using the same plugin, go to one of those websites that haven’t updated the plugin yet.
- Access the plugin files via FTP or your hosting control panel (cPanel or similar).
- Download the folder for the older version of the All in One SEO plugin, in this case, version 4.6.9.1. or get Version 4.7.0 incase you don’t have where to download old version. Link below
- http://downloads.wordpress.org/plugin/all-in-one-seo-pack.4.7.0.zip
- Upload the Older Version to Your Website:
- Access the website showing the error via FTP or cPanel.
- Navigate to the
wp-content/pluginsdirectory. - Delete the existing All in One SEO plugin folder to avoid any conflicts.
- Upload the older plugin folder you downloaded in the previous step.
- Once the upload is complete, log in to your WordPress dashboard and activate the plugin if it isn’t already active.
- Check Your Website:
- Refresh your website to see if the error message is gone.
- Ensure that all SEO settings and data are intact. Downgrading should not usually affect your existing settings, but it’s good to double-check.
Option 2: Remove the Plugin and Use an Alternative
If you don’t want to downgrade or if the problem persists, you may consider removing the All in One SEO plugin entirely and switching to an alternative SEO plugin like Rank Math or Yoast SEO. Keep in mind that removing the plugin might affect your website’s titles and descriptions, especially if you’ve already optimized your content.
- Deactivate and Delete All in One SEO Plugin:
- Go to your WordPress dashboard, navigate to ‘Plugins,’ and deactivate the All in One SEO plugin.
- After deactivating, click ‘Delete’ to remove it completely from your website.
- Install an Alternative SEO Plugin:
- Go to ‘Plugins’ > ‘Add New’ in your WordPress dashboard.
- Search for Rank Math or Yoast SEO, which are popular alternatives.
- Install and activate the new SEO plugin of your choice.
- Reconfigure SEO Settings:
- Go through the setup process of the new plugin and reconfigure your SEO settings.
- Some plugins have import tools that can transfer your existing SEO settings from the old plugin to the new one, which can save time and ensure consistency.
Option 3: Troubleshoot and Debug (Advanced)
If you want to troubleshoot further without downgrading or removing the plugin, you can try to debug the issue:
- Check for Theme or Plugin Conflicts:
- Temporarily switch to a default WordPress theme like Twenty Twenty-One and disable other plugins to see if the error persists.
- If the error disappears, reactivate your theme and plugins one by one to identify the conflicting element.
- Enable WP_DEBUG:
- Add the following line to your
wp-config.phpfile to enable debugging:php
- Add the following line to your
