Title: Undefined function related_posts() in single.php
Last modified: August 21, 2016

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# Undefined function related_posts() in single.php

 *  [JuanR](https://wordpress.org/support/users/juanr/)
 * (@juanr)
 * [12 years, 2 months ago](https://wordpress.org/support/topic/undefined-function-related_posts-in-singlephp/)
 * Hi, I have some problems using YARPP plugin in my wordpress site, I have the 
   thematic theme and the wordpress is multi user.
    I need to add the related_posts
   function in my homepage and in each single post page. I added and activated the
   plugin in my WP and I added the related_posts function in the header.php. For
   some reason in the homepage the plugin works fine but in others pages e.g post
   page (single.php) the site returns me undefined function related_posts(). I dont
   know what is the problem 🙁
 * Thanks!! your comments will be appreciated!
 * [https://wordpress.org/plugins/yet-another-related-posts-plugin/](https://wordpress.org/plugins/yet-another-related-posts-plugin/)

Viewing 1 replies (of 1 total)

 *  Thread Starter [JuanR](https://wordpress.org/support/users/juanr/)
 * (@juanr)
 * [12 years, 2 months ago](https://wordpress.org/support/topic/undefined-function-related_posts-in-singlephp/#post-4749981)
 * I post the error here:
 * Fatal error: Call to undefined function related_posts()

Viewing 1 replies (of 1 total)

The topic ‘Undefined function related_posts() in single.php’ is closed to new replies.

 * ![](https://ps.w.org/yet-another-related-posts-plugin/assets/icon-256x256.png?
   rev=2549977)
 * [YARPP - Yet Another Related Posts Plugin](https://wordpress.org/plugins/yet-another-related-posts-plugin/)
 * [Frequently Asked Questions](https://wordpress.org/plugins/yet-another-related-posts-plugin/#faq)
 * [Support Threads](https://wordpress.org/support/plugin/yet-another-related-posts-plugin/)
 * [Active Topics](https://wordpress.org/support/plugin/yet-another-related-posts-plugin/active/)
 * [Unresolved Topics](https://wordpress.org/support/plugin/yet-another-related-posts-plugin/unresolved/)
 * [Reviews](https://wordpress.org/support/plugin/yet-another-related-posts-plugin/reviews/)

## Tags

 * [thematic](https://wordpress.org/support/topic-tag/thematic/)
 * [YARPP](https://wordpress.org/support/topic-tag/yarpp/)

 * 1 reply
 * 1 participant
 * Last reply from: [JuanR](https://wordpress.org/support/users/juanr/)
 * Last activity: [12 years, 2 months ago](https://wordpress.org/support/topic/undefined-function-related_posts-in-singlephp/#post-4749981)
 * Status: not resolved