Title: PHP Mb String Fatal Error
Last modified: June 9, 2018

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# PHP Mb String Fatal Error

 *  Resolved [John Darrel](https://wordpress.org/support/users/johndarrel/)
 * (@johndarrel)
 * [8 years ago](https://wordpress.org/support/topic/php-mb-string-fatal-error/)
 * Hi,
 * Great cache plugin. We’re working to make [https://wordpress.org/plugins/hide-my-wp/](https://wordpress.org/plugins/hide-my-wp/)
   compatible with your plugin and I noticed that we get a Fatal error when the 
   mbstring extension in PHP is not activated.
 * Fatal error: Uncaught Error: Call to undefined function mb_substr() in \wp-content\
   plugins\powered-cache\includes\dropins\page-cache.php:437
 * I know it’s something easy to fix.
 * I will definitely recommend your plugin in the future … hope you will recommend
   our plugin too for security.

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

 *  Plugin Author [Mustafa Uysal](https://wordpress.org/support/users/m_uysl/)
 * (@m_uysl)
 * [8 years ago](https://wordpress.org/support/topic/php-mb-string-fatal-error/#post-10382886)
 * Hello [@johndarrel](https://wordpress.org/support/users/johndarrel/),
 * Thanks for good thoughts.
 * > [https://wordpress.org/plugins/hide-my-wp/](https://wordpress.org/plugins/hide-my-wp/)
   > compatible with your plugin and I noticed that we get a Fatal error when the
   > mbstring extension in PHP is not activated.
 * Well, actually WordPress has a compat function for `mb_substr()`. I don’t know
   why the fatal error raised, but I’m going to check this.
 * > I will definitely recommend your plugin in the future … hope you will recommend
   > our plugin too for security.
 * Probably, your plugin helps to avoid script kiddie attacks, but I usually don’t
   recommend any of WordPress plugins for the security 🙂
 * Thanks.
 *  Plugin Author [Mustafa Uysal](https://wordpress.org/support/users/m_uysl/)
 * (@m_uysl)
 * [7 years, 12 months ago](https://wordpress.org/support/topic/php-mb-string-fatal-error/#post-10384127)
 * Hi, [@johndarrel](https://wordpress.org/support/users/johndarrel/)
 * I just released the new version that fixes the issue you’ve mentioned above. 
   Thanks for the reporting.
 * Cheers,

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

The topic ‘PHP Mb String Fatal Error’ is closed to new replies.

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 * [Powered Cache – Caching and Optimization for WordPress – Easily Improve PageSpeed & Web Vitals Score](https://wordpress.org/plugins/powered-cache/)
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 * 2 replies
 * 2 participants
 * Last reply from: [Mustafa Uysal](https://wordpress.org/support/users/m_uysl/)
 * Last activity: [7 years, 12 months ago](https://wordpress.org/support/topic/php-mb-string-fatal-error/#post-10384127)
 * Status: resolved