Title: Function ‘markdown_script’ not found or invalid name in class-wp-hook.php
Last modified: February 20, 2017

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# Function ‘markdown_script’ not found or invalid name in class-wp-hook.php

 *  Resolved [Eric P.](https://wordpress.org/support/users/codeep/)
 * (@codeep)
 * [9 years, 3 months ago](https://wordpress.org/support/topic/function-markdown_script-not-found-or-invalid-name-in-class-wp-hook-php/)
 * Hi there,
 * I recently upgraded my site from PHP 5.6.13 to PHP version 7.1.1, and found this
   warning on every wp-admin page showing at the top:
 * `Warning: call_user_func_array() expects parameter 1 to be a valid callback, 
   function 'markdown_script' not found or invalid function name in /www/wp-includes/
   class-wp-hook.php on the line 298`
 * Since before the upgrade I’ve never encountered this error and everything worked
   just fine (WordPress 4.7.2 on PHP 5.6.13), I am wondering whether I configured&
   compiled something wrong or just the latest version of PHP doesn’t work well 
   with WP 4.7.2 …
 * Besides, Markdown translation still works (I installed “JP Markdown” plugin).
 * Looking forward to a prompt support, thanks!

Viewing 2 replies - 1 through 2 (of 2 total)

 *  Thread Starter [Eric P.](https://wordpress.org/support/users/codeep/)
 * (@codeep)
 * [9 years, 3 months ago](https://wordpress.org/support/topic/function-markdown_script-not-found-or-invalid-name-in-class-wp-hook-php/#post-8849291)
 * Is there anyone that is able to help me QAQ ..or just some direction of suspicions
   for me to modify and test my site.
 * Thanks a lot!
 *  Thread Starter [Eric P.](https://wordpress.org/support/users/codeep/)
 * (@codeep)
 * [9 years, 3 months ago](https://wordpress.org/support/topic/function-markdown_script-not-found-or-invalid-name-in-class-wp-hook-php/#post-8873356)
 * ![_(:з」∠)_](https://i0.wp.com/cdn.ericp.cn/wp-content/uploads/2017/03/Makiorz.
   jpg)

Viewing 2 replies - 1 through 2 (of 2 total)

The topic ‘Function ‘markdown_script’ not found or invalid name in class-wp-hook.
php’ is closed to new replies.

## Tags

 * [call_user_func_array](https://wordpress.org/support/topic-tag/call_user_func_array/)

 * In: [Fixing WordPress](https://wordpress.org/support/forum/how-to-and-troubleshooting/)
 * 2 replies
 * 1 participant
 * Last reply from: [Eric P.](https://wordpress.org/support/users/codeep/)
 * Last activity: [9 years, 3 months ago](https://wordpress.org/support/topic/function-markdown_script-not-found-or-invalid-name-in-class-wp-hook-php/#post-8873356)
 * Status: resolved

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