Title: WordPress admin error class-addon-manager.php
Last modified: April 22, 2019

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# WordPress admin error class-addon-manager.php

 *  Resolved [mac2025](https://wordpress.org/support/users/mac2025/)
 * (@mac2025)
 * [7 years, 1 month ago](https://wordpress.org/support/topic/wordpress-admin-error-class-addon-manager-php/)
 * I receive the error below when accessing the WordPress admin. I’ve deleted Yoast
   and reinstalled which fixes the issue for 1 day, then the error comes back 1 
   day later each time.
 * Fatal error: Uncaught Error: Call to undefined function get_plugins() in ……wp-
   content/plugins/wordpress-seo/inc/class-addon-manager.php:444

Viewing 5 replies - 1 through 5 (of 5 total)

 *  [cybermyber](https://wordpress.org/support/users/cybermyber/)
 * (@cybermyber)
 * [7 years, 1 month ago](https://wordpress.org/support/topic/wordpress-admin-error-class-addon-manager-php/#post-11462146)
 * I have the same issue
 *  [devnihil](https://wordpress.org/support/users/devnihil/)
 * (@devnihil)
 * [7 years, 1 month ago](https://wordpress.org/support/topic/wordpress-admin-error-class-addon-manager-php/#post-11463544)
 * Can you please confirm you are using the most recent Yoast v11.0? You can learn
   more about updating here: [https://kb.yoast.com/kb/how-can-i-update-my-free-plugin/](https://kb.yoast.com/kb/how-can-i-update-my-free-plugin/)
 * Can you confirm you are using WordPress 5.1.1? You can check by clicking on the
   W in the top left and selecting About. If you need to update, please check with
   your host provider. Please know that if you are using an older version of WordPress
   Core you may experience unexpected behavior with Yoast. This guide explains more:
   [https://yoast.com/why-we-dont-support-old-wordpress-versions/](https://yoast.com/why-we-dont-support-old-wordpress-versions/)
   ​​
   If you update to the most current version of WordPress and Yoast SEO, does this
   resolve the issue?
 * If the issue is still occurring after confirming both Yoast SEO and WordPress
   are updated, this may be due to a plugin or theme conflict. Can you try and gather
   as much information for us as possible? Please perform the following:
 * 1. [Check for conflicts](https://kb.yoast.com/kb/how-to-check-for-plugin-conflicts).
   
   2. Check for [JavaScript errors with your console](https://kb.yoast.com/kb/how-to-find-javascript-errors-with-your-browsers-console).
   If you find any JavaScript errors related to Yoast SEO or if there is a conflict
   with a plugin or a theme, you can create a [new GitHub issue](https://github.com/Yoast/wordpress-seo/issues/new)
   for our developers. Please report the issue to a third party developer as well.
 * If you didn’t find any conflicts or errors, we think the issue is specific to
   your site. We’d need to investigate further but are unable to do so on these 
   forums. You can [purchase Yoast SEO Premium](https://yoast.com/wordpress/plugins/seo/)
   and receive our Premium email support and we can help you further.
 *  Thread Starter [mac2025](https://wordpress.org/support/users/mac2025/)
 * (@mac2025)
 * [7 years, 1 month ago](https://wordpress.org/support/topic/wordpress-admin-error-class-addon-manager-php/#post-11467010)
 * Thanks for your reply. Currently on WP version 5.1.1. I removed the wordpress-
   seo folder in plugins and reinstalled latest version of Yoast. All works fine,
   but the next day I get this error message. I’ve done this process twice with 
   the same results.
 * I will try some of the other steps you’ve outlined. Thanks
 *  [devnihil](https://wordpress.org/support/users/devnihil/)
 * (@devnihil)
 * [7 years ago](https://wordpress.org/support/topic/wordpress-admin-error-class-addon-manager-php/#post-11486615)
 * Were you able to perform a conflict check to see whether this error was the result
   of a conflicting plugin or theme?
 *  Thread Starter [mac2025](https://wordpress.org/support/users/mac2025/)
 * (@mac2025)
 * [7 years ago](https://wordpress.org/support/topic/wordpress-admin-error-class-addon-manager-php/#post-11486667)
 * I was able to find 1 plugin, when deactivated fixed the error message I was receiving.
   The issue is it’s a plugin that has quite a bit of functionality in the website(
   this was setup by another developer). So it’s won’t be as easy as removing the
   plugin. I’ll need to think about how to proceed, but it doesn’t appear to be 
   a Yoast issue. Thank you for your help, and sorry I’ve brought you in when it
   wasn’t a Yoast issue.
 * Dan

Viewing 5 replies - 1 through 5 (of 5 total)

The topic ‘WordPress admin error class-addon-manager.php’ is closed to new replies.

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 * 5 replies
 * 3 participants
 * Last reply from: [mac2025](https://wordpress.org/support/users/mac2025/)
 * Last activity: [7 years ago](https://wordpress.org/support/topic/wordpress-admin-error-class-addon-manager-php/#post-11486667)
 * Status: resolved