Title: fatal error when mbstring package is missing
Last modified: August 31, 2016

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# fatal error when mbstring package is missing

 *  Resolved [nosilver4u](https://wordpress.org/support/users/nosilver4u/)
 * (@nosilver4u)
 * [10 years ago](https://wordpress.org/support/topic/fatal-error-when-mbstring-package-is-missing/)
 * Couldn’t figure out why Cache Enabler’s webp option wasn’t working on my dev 
   server until I checked the error logs. Found this:
 * `PHP Fatal error: Uncaught Error: Call to undefined function mb_convert_encoding()
   in /var/www/html/wordpress/wp-content/plugins/cache-enabler/inc/cache_enabler_disk.
   class.php:525...`
 * Turns out Ubuntu doesn’t include php-mbstring by default when you install PHP,
   and from searching around, seems other linux distros are doing similar things
   in newer versions.
 * It would be nice if Cache Enabler would check to make sure the function exists
   instead of causing fatal errors, and perhaps you could even throw an admin notice
   if someone is missing the function(s).
 * [https://wordpress.org/plugins/cache-enabler/](https://wordpress.org/plugins/cache-enabler/)

Viewing 1 replies (of 1 total)

 *  Plugin Author [KeyCDN](https://wordpress.org/support/users/keycdn/)
 * (@keycdn)
 * [10 years ago](https://wordpress.org/support/topic/fatal-error-when-mbstring-package-is-missing/#post-7381192)
 * Good catch, thanks! Added a check and showing an admin message if it is missing.

Viewing 1 replies (of 1 total)

The topic ‘fatal error when mbstring package is missing’ is closed to new replies.

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## Tags

 * [cache](https://wordpress.org/support/topic-tag/cache/)
 * [mbstring](https://wordpress.org/support/topic-tag/mbstring/)
 * [webp](https://wordpress.org/support/topic-tag/webp/)

 * 1 reply
 * 2 participants
 * Last reply from: [KeyCDN](https://wordpress.org/support/users/keycdn/)
 * Last activity: [10 years ago](https://wordpress.org/support/topic/fatal-error-when-mbstring-package-is-missing/#post-7381192)
 * Status: resolved