Title: PHP error in version 3.9.1
Last modified: August 21, 2016

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# PHP error in version 3.9.1

 *  [veg-o-matic](https://wordpress.org/support/users/veg-o-matic/)
 * (@veg-o-matic)
 * [11 years, 12 months ago](https://wordpress.org/support/topic/php-error-in-version-391/)
 * I started getting this error back in version 3.7.X and despite a couple of upgrades,
   it won’t go away.
    Oddly, it only occurs with two of our 15 blogs, all running
   on the same machine, all with the same version of WP
 * > [Wed Jun 04 08:17:15 2014] [error] [client 10.1.7.30] PHP Warning: json_encode():
   > Invalid UTF-8 sequence in argument in /srv/www/ht
   >  docs/path/to/blog/wp-includes/
   > update.php on line 270
 * Anyone got any ideas? TIA!

Viewing 6 replies - 1 through 6 (of 6 total)

 *  [esmi](https://wordpress.org/support/users/esmi/)
 * (@esmi)
 * [11 years, 12 months ago](https://wordpress.org/support/topic/php-error-in-version-391/#post-4978672)
 * Have you tried:
 * – deactivating **all** plugins to see if this resolves the problem. If this works,
   re-activate the plugins one by one until you find the problematic plugin(s).
 * – switching to the default theme to rule out any theme-specific problems.
 * – [resetting the plugins folder](http://codex.wordpress.org/FAQ_Troubleshooting#How_to_deactivate_all_plugins_when_not_able_to_access_the_administrative_menus.3F)
   by FTP or PhpMyAdmin. Sometimes, an apparently inactive plugin can still cause
   problems.
 * – re-uploading all files & folders – **except** the wp-content folder and wp-
   config.php & root .htaccess files – from a **fresh** download of WordPress. Make
   sure that you delete the old copies of files & folder before uploading the new
   ones.
 *  [Peter Lawrenson](https://wordpress.org/support/users/lorro/)
 * (@lorro)
 * [11 years, 11 months ago](https://wordpress.org/support/topic/php-error-in-version-391/#post-4978801)
 * Check for non-UTF8 characters in your post text. Candidates include smart/curling
   inverted commas (replace with the vertical type), the slanted apostrophe (replace
   with the vertical one) and the longer hyphen favoured by MS Word (replace with
   the minus sign which is only fractionally shorter).
 * Sometimes if you put /feed at the end of the page url, the feed will break giving
   an error message with the exact point of the invalid character.
 *  Thread Starter [veg-o-matic](https://wordpress.org/support/users/veg-o-matic/)
 * (@veg-o-matic)
 * [11 years, 11 months ago](https://wordpress.org/support/topic/php-error-in-version-391/#post-4978815)
 * esmi: I have done everything you suggested and I still get the error.
 * lorro: the problem doesn’t seem to be in a post, but in update.php.
 * Still very confused…
 *  [Peter Lawrenson](https://wordpress.org/support/users/lorro/)
 * (@lorro)
 * [11 years, 11 months ago](https://wordpress.org/support/topic/php-error-in-version-391/#post-4978816)
 * Yes, I’ve had another look. Line 270 is getting an array of plugin data. The 
   plugin data comes from each plugin’s primary file which has some comments in 
   the top 20 or so lines, giving Name, PluginURI, Version, Description, Author 
   etc.
 * So to identify which plugin it is, rename the plugins folder to say old_plugins.
   If this removes the error message, create a new empty folder called plugins and
   move the plugins back one at a time to try and identify the plugin that’s causing
   the problem. Then examine the plugin’s primary file comments lines to look for
   non UTF8 characters.
 * Deactivating the plugins is not sufficient for this test.
 *  [simanonok](https://wordpress.org/support/users/simanonok/)
 * (@simanonok)
 * [11 years, 8 months ago](https://wordpress.org/support/topic/php-error-in-version-391/#post-4978960)
 * lorro, what will ‘non UTF8’ characters look like? Don’t a lot of them LOOK like
   UTF8’s? I really doubt I’d be able to scan every file of a plugin visually and
   find every one that might be hidden there. I think my old version of Textpad 
   can be set to force saved files into UTF8 format, so do you think I could I load
   and resave every file for a plugin to get rid of the problem?
 *  [simanonok](https://wordpress.org/support/users/simanonok/)
 * (@simanonok)
 * [11 years, 8 months ago](https://wordpress.org/support/topic/php-error-in-version-391/#post-4978961)
 * It appears that the problem may trace to the MySQL databases’s default character
   set being latin1 instead of UTF-8. How lovely…

Viewing 6 replies - 1 through 6 (of 6 total)

The topic ‘PHP error in version 3.9.1’ is closed to new replies.

## Tags

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

 * In: [Fixing WordPress](https://wordpress.org/support/forum/how-to-and-troubleshooting/)
 * 6 replies
 * 4 participants
 * Last reply from: [simanonok](https://wordpress.org/support/users/simanonok/)
 * Last activity: [11 years, 8 months ago](https://wordpress.org/support/topic/php-error-in-version-391/#post-4978961)
 * Status: not resolved

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