Title: Fatal Error when activated plugin after update
Last modified: September 20, 2021

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# Fatal Error when activated plugin after update

 *  Resolved [Local](https://wordpress.org/support/users/fullctrl/)
 * (@fullctrl)
 * [4 years, 7 months ago](https://wordpress.org/support/topic/fatal-error-when-activated-plugin-after-update/)
 * Hi,
 * We had some problem with the plugin on a page, but then I managed to increase
   the memory limit and execution time, and it worked fine for about an hour, but
   then received an WordPress Technical issue email with following error caused 
   by Yoast SEO:
 * An error of type E_ERROR was caused in line 160 of the file /home/2/s/XXXXXX/
   www/wp-content/plugins/wordpress-seo/src/initializers/migration-runner.php.
    
   Error message: Uncaught Error: Class ‘Yoast\WP\SEO\Config\Migrations\CreateIndexableSubpagesIndex’
   not found in /home/2/s/xxxxxx/www/wp-content/plugins/wordpress-seo/src/initializers/
   migration-runner.php:160
 * I did update it manually through FTP.
    WordPress version 5.8.1 Current plugin:
   Yoast SEO (version 17.1) PHP version 7.4.23
 * Can you advise what to do about this please?
 * Kind regards,

Viewing 4 replies - 1 through 4 (of 4 total)

 *  Plugin Support [Michael Tiña](https://wordpress.org/support/users/mikes41720/)
 * (@mikes41720)
 * [4 years, 7 months ago](https://wordpress.org/support/topic/fatal-error-when-activated-plugin-after-update/#post-14892067)
 * Hi [@fullctrl](https://wordpress.org/support/users/fullctrl/)
 * We’re sorry to hear that the Yoast SEO plugin isn’t working as intended.
 * We do see that you are on the latest version of WordPress 5.8.1 and Yoast SEO
   17.1, and have PHP version 7.4.23.
 * Could you check if the rest of your plugins and themes are up-to-date and you
   are also meeting the rest of the [plugin requirements](https://yoast.com/help/plugin-requirements/)?
 * Based on the error message, it looks like there is a missing file. Would it be
   possible for you to remove the plugin and download a fresh copy of Yoast SEO 
   for WordPress 17.1 and [install it via FTP](https://yoast.com/help/how-can-i-update-my-free-plugin/#ftp)
   and see if this resolves the issue?
 *  Thread Starter [Local](https://wordpress.org/support/users/fullctrl/)
 * (@fullctrl)
 * [4 years, 7 months ago](https://wordpress.org/support/topic/fatal-error-when-activated-plugin-after-update/#post-14894814)
 * Hi Michael,
 * Yes, all the plugin requirements are up-to-date.
 * I did install the fresh 17.2 version via FTP, and it’s lasted me all day today
   so that is progress 🙂 Let’s hope this works then!
 *  [devnihil](https://wordpress.org/support/users/devnihil/)
 * (@devnihil)
 * [4 years, 7 months ago](https://wordpress.org/support/topic/fatal-error-when-activated-plugin-after-update/#post-14898225)
 * [@fullctrl](https://wordpress.org/support/users/fullctrl/) Thanks for your reply,
   and we’re glad to hear that reinstalling the 17.2 version of the plugins seems
   to have corrected the issue for you. If you should need any further assistance,
   please do not hesitate to let us know.
 *  [devnihil](https://wordpress.org/support/users/devnihil/)
 * (@devnihil)
 * [4 years, 7 months ago](https://wordpress.org/support/topic/fatal-error-when-activated-plugin-after-update/#post-14925212)
 * We are going ahead and marking this issue as resolved due to inactivity. If you
   require any further assistance please create a new issue.

Viewing 4 replies - 1 through 4 (of 4 total)

The topic ‘Fatal Error when activated plugin after update’ is closed to new replies.

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 * [Yoast SEO - Advanced SEO with real-time guidance and built-in AI](https://wordpress.org/plugins/wordpress-seo/)
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 * 4 replies
 * 3 participants
 * Last reply from: [devnihil](https://wordpress.org/support/users/devnihil/)
 * Last activity: [4 years, 7 months ago](https://wordpress.org/support/topic/fatal-error-when-activated-plugin-after-update/#post-14925212)
 * Status: resolved