Title: PHP Warning:  json_encode(): Invalid UTF-8 sequence in argument
Last modified: August 22, 2016

---

# PHP Warning: json_encode(): Invalid UTF-8 sequence in argument

 *  Resolved [linux4me2](https://wordpress.org/support/users/linux4me2/)
 * (@linux4me2)
 * [11 years, 6 months ago](https://wordpress.org/support/topic/php-warning-json_encode-invalid-utf-8-sequence-in-argument/)
 * This one really has me scratching my head.
 * I have [a site](http://thearmariumpress.com/) whose error log is filling up with
   PHP warnings like this:
 *     ```
       PHP Warning:  json_encode(): Invalid UTF-8 sequence in argument in /home/theusername/public_html/wp-includes/class.wp-scripts.php on line 170
       ```
   
 * It has been particularly hard to troubleshoot because I can’t reproduce the error
   by browsing to a particular post or page, though the warning keeps showing up
   in the error logs.
 * I’ve searched for this error message but haven’t found an issue involving class.
   wp-scripts.php. It looks like class.wp-scripts.php handles the enqueueing of 
   scripts, and I don’t see a script name for the site that includes an invalid 
   UTF-8 character.
 * Does anyone have any idea how I might identify the cause of this warning and 
   fix it?

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

 *  [k-theory](https://wordpress.org/support/users/k-theory/)
 * (@k-theory)
 * [11 years, 6 months ago](https://wordpress.org/support/topic/php-warning-json_encode-invalid-utf-8-sequence-in-argument/#post-5527447)
 * I’m getting the same error on a production server… I cannot recreate or find 
   the culprit. Any ideas would be greatly appreciated!
 *  Moderator [Jose Castaneda](https://wordpress.org/support/users/jcastaneda/)
 * (@jcastaneda)
 * THEME COFFEE MONKEY
 * [11 years, 6 months ago](https://wordpress.org/support/topic/php-warning-json_encode-invalid-utf-8-sequence-in-argument/#post-5527448)
 * Does this happen with all plugins deactivated and a bundled theme like Twenty
   Fourteen or Twenty Thirteen?
 *  Thread Starter [linux4me2](https://wordpress.org/support/users/linux4me2/)
 * (@linux4me2)
 * [11 years, 6 months ago](https://wordpress.org/support/topic/php-warning-json_encode-invalid-utf-8-sequence-in-argument/#post-5527456)
 * I’m so glad it’s not just me!
 * I’m running the Twenty Ten theme on the problem site. I am not in a position 
   to deactivate all plugins because this is a production site, but it isn’t running
   any plugins that I’m not running in the same combination on another site that
   isn’t throwing the warning.
 * If I get a chance today, I’m going to try adding some code to class.wp-scripts.
   php to record the values of $l10n in the problem line:
 *     ```
       $script = "var $object_name = " . json_encode($l10n) . ';';
       ```
   
 * to see if I can figure out which one contains an invalid UTF-8 sequence and trace
   it back that way.
 *  Thread Starter [linux4me2](https://wordpress.org/support/users/linux4me2/)
 * (@linux4me2)
 * [11 years, 6 months ago](https://wordpress.org/support/topic/php-warning-json_encode-invalid-utf-8-sequence-in-argument/#post-5527460)
 * I put the code in to catch the invalid UTF-8 sequences and discovered a couple
   of things. First, the reason I wasn’t able to reproduce the error appears to 
   be that someone is apparently submitting an array of arrays to the WP_Scripts
   function, and some of the values for the secondary arrays are invalid UTF-8 strings
   including a variety of strings that aren’t script names, spammy stuff with URLs
   to spammer sites, etc.
 * I reviewed the site’s traffic logs and noticed a huge upswing in traffic from
   a particular country well-known for spam/hacking that corresponds to the time
   this site has been throwing the warning.
 * It doesn’t look like it has to do with WordPress after all, or at least not in
   the sense that the warning represents something wrong with the site.

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

The topic ‘PHP Warning: json_encode(): Invalid UTF-8 sequence in argument’ is closed
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## Tags

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

 * In: [Fixing WordPress](https://wordpress.org/support/forum/how-to-and-troubleshooting/)
 * 4 replies
 * 3 participants
 * Last reply from: [linux4me2](https://wordpress.org/support/users/linux4me2/)
 * Last activity: [11 years, 6 months ago](https://wordpress.org/support/topic/php-warning-json_encode-invalid-utf-8-sequence-in-argument/#post-5527460)
 * Status: resolved

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