Title: Fatal error when activating plugin
Last modified: June 8, 2020

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# Fatal error when activating plugin

 *  [touchestudio](https://wordpress.org/support/users/boulosblack/)
 * (@boulosblack)
 * [6 years ago](https://wordpress.org/support/topic/fatal-error-when-activating-plugin-59/)
 * Hello,
 * I’m getting this error when I try and activate the plugin:
 * Fatal error: Cannot redeclare wp_cache_add() (previously declared in …/public_html/
   wp-content/object-cache.php:18) in …/public_html/wp-content/plugins/memcached-
   redux/object-cache.php on line 18
 * Hoping you can help me get it working.
 * Best regards,
 * Paul

Viewing 3 replies - 1 through 3 (of 3 total)

 *  Plugin Contributor [Ipstenu (Mika Epstein)](https://wordpress.org/support/users/ipstenu/)
 * (@ipstenu)
 * 🏳️‍🌈 Advisor and Activist
 * [6 years ago](https://wordpress.org/support/topic/fatal-error-when-activating-plugin-59/#post-12957410)
 * Please re-read the documentation.
 * [https://wordpress.org/plugins/memcached-redux/#installation](https://wordpress.org/plugins/memcached-redux/#installation)
 * You don’t activate this normally.
 *  Thread Starter [touchestudio](https://wordpress.org/support/users/boulosblack/)
 * (@boulosblack)
 * [5 years, 12 months ago](https://wordpress.org/support/topic/fatal-error-when-activating-plugin-59/#post-12965401)
 * Hi [@ipstenu](https://wordpress.org/support/users/ipstenu/) ,
 * Thanks for the tip. The first thing I did before installing it was read the 3
   bullet point documentation.
 * Which part of it caused this fatal error?
 *  Plugin Contributor [Ipstenu (Mika Epstein)](https://wordpress.org/support/users/ipstenu/)
 * (@ipstenu)
 * 🏳️‍🌈 Advisor and Activist
 * [5 years, 12 months ago](https://wordpress.org/support/topic/fatal-error-when-activating-plugin-59/#post-12966333)
 * You said you tried to activate. That would be why.
 * You don’t activate this.
 * Step 3 is “Copy object-cache.php to wp-content”
 * That’s it. You’re done 🙂
 * There should be a step 4 “Do not activate via wp-admin”

Viewing 3 replies - 1 through 3 (of 3 total)

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

 * ![](https://s.w.org/plugins/geopattern-icon/memcached-redux_98a1ab.svg)
 * [Memcached Redux](https://wordpress.org/plugins/memcached-redux/)
 * [Support Threads](https://wordpress.org/support/plugin/memcached-redux/)
 * [Active Topics](https://wordpress.org/support/plugin/memcached-redux/active/)
 * [Unresolved Topics](https://wordpress.org/support/plugin/memcached-redux/unresolved/)
 * [Reviews](https://wordpress.org/support/plugin/memcached-redux/reviews/)

 * 3 replies
 * 2 participants
 * Last reply from: [Ipstenu (Mika Epstein)](https://wordpress.org/support/users/ipstenu/)
 * Last activity: [5 years, 12 months ago](https://wordpress.org/support/topic/fatal-error-when-activating-plugin-59/#post-12966333)
 * Status: not resolved