Title: Fatal error
Last modified: December 1, 2022

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# Fatal error

 *  [Daschmi](https://wordpress.org/support/users/daschmi/)
 * (@daschmi)
 * [3 years, 4 months ago](https://wordpress.org/support/topic/fatal-error-4309/)
 * Not working PHP8

Viewing 7 replies - 1 through 7 (of 7 total)

 *  Plugin Contributor [Andrija Vučinić](https://wordpress.org/support/users/aidvu/)
 * (@aidvu)
 * [3 years, 4 months ago](https://wordpress.org/support/topic/fatal-error-4309/#post-16251925)
 * Hi, what is not working? 🙂 How did you install?
 *  [ohgoodiee](https://wordpress.org/support/users/ohgoodiee/)
 * (@ohgoodiee)
 * [3 years, 4 months ago](https://wordpress.org/support/topic/fatal-error-4309/#post-16258126)
 * Same issue
 * Fatal error: Cannot redeclare wp_cache_add() (previously declared in /var/www/
   html/9438/wp-includes/cache.php:41) in /var/www/html/9438/wp-content/plugins/
   memcached/object-cache.php on line 19
 *  Plugin Contributor [Andrija Vučinić](https://wordpress.org/support/users/aidvu/)
 * (@aidvu)
 * [3 years, 4 months ago](https://wordpress.org/support/topic/fatal-error-4309/#post-16266069)
 * Did you look at the installation guide? 🙂 [https://wordpress.org/plugins/memcached/#installation](https://wordpress.org/plugins/memcached/#installation)
 *  [Marian Kadanka](https://wordpress.org/support/users/mariankadanka/)
 * (@mariankadanka)
 * [3 years, 4 months ago](https://wordpress.org/support/topic/fatal-error-4309/#post-16271974)
 * Give it up guys, use [https://wordpress.org/plugins/use-memcached/](https://wordpress.org/plugins/use-memcached/)
   which just works, doesn’t need PECL extension and copy object-cache.php itself.
 *  [grindlay](https://wordpress.org/support/users/grindlay/)
 * (@grindlay)
 * [3 years, 4 months ago](https://wordpress.org/support/topic/fatal-error-4309/#post-16279481)
 * Folks, having used the `object-cache.php` file today, a few comments.
    You only
   need the one file, no need to install the plugin via the usual routine. I had
   to manually generate a 64-char random string for the `wp_config.php` file. On
   my server, I made the mistake of confusing `memcache` with `memcached`. Install**
   memcached** on the server first. If you use WHM, you can use `Module Installers
   > PHP PECL Installer` to install the **Memcache **module. Remember that you need
   to do this for all the versions of PHP on your system. So, server first, install
   memcached and test. Next, install memcache PECL module. (Remember to restart 
   your webserver/php-fpm for changes to take effect) Finally, copy `object-cache.
   php` to you /wp-content folder. Good luck.
 *  [dgswim](https://wordpress.org/support/users/dgswim/)
 * (@dgswim)
 * [3 years, 4 months ago](https://wordpress.org/support/topic/fatal-error-4309/#post-16303749)
 * This person below is right. Just download the plugin, install it and use it. 
   I struggled to make this above particular plugin or method work for a long time.
   I have come back to it many times and tried so many times. Just did not work.
   This plugin below does. It is simple. Be sure to get rid of the garbage these
   guys tell you to put in your config file. If you dont this plugin will not work.
   I remembered and took this junk out, saved and the plugin below worked right 
   away. I was so happy I spent the time to reset my password here just to tell 
   about it.
 * [Marian Kadanka](https://wordpress.org/support/users/mariankadanka/) 
 * (@mariankadanka)
 * [1 week, 4 days ago](https://wordpress.org/support/topic/fatal-error-4309/#post-16271974)
 * Give it up guys, use [https://wordpress.org/plugins/use-memcached/](https://wordpress.org/plugins/use-memcached/)
   which just works, doesn’t need PECL extension and copy object-cache.php itself.
 *  [ulicgn](https://wordpress.org/support/users/ulicgn/)
 * (@ulicgn)
 * [2 years, 11 months ago](https://wordpress.org/support/topic/fatal-error-4309/#post-16688485)
 * Note: The plugin recommended by [@dgswim](https://wordpress.org/support/users/dgswim/)
   [@mariankadanka](https://wordpress.org/support/users/mariankadanka/) is not maintained
   any more and also not update for some years now.

Viewing 7 replies - 1 through 7 (of 7 total)

The topic ‘Fatal error’ is closed to new replies.

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 * 7 replies
 * 7 participants
 * Last reply from: [ulicgn](https://wordpress.org/support/users/ulicgn/)
 * Last activity: [2 years, 11 months ago](https://wordpress.org/support/topic/fatal-error-4309/#post-16688485)