Title: Fatal error: Cannot redeclare wp_cache_add()
Last modified: September 7, 2020

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# Fatal error: Cannot redeclare wp_cache_add()

 *  [Alexandre Froger](https://wordpress.org/support/users/frogerme/)
 * (@frogerme)
 * [5 years, 9 months ago](https://wordpress.org/support/topic/fatal-error-cannot-redeclare-wp_cache_add/)
 * Hi!
 * I get the following error on activation:
 * >  Fatal error: Cannot redeclare wp_cache_add() (previously declared in /wp-includes/
   > cache.php:30) in /wp-content/plugins/memcached/object-cache.php on line 23
 * Any advice?

Viewing 4 replies - 1 through 4 (of 4 total)

 *  [asterix30](https://wordpress.org/support/users/asterix30/)
 * (@asterix30)
 * [5 years, 8 months ago](https://wordpress.org/support/topic/fatal-error-cannot-redeclare-wp_cache_add/#post-13520082)
 * Same issue here:
    Fatal error: Cannot redeclare wp_cache_add() (previously declared
   in /var/www/vhosts/domain.com/httpdocs/wp-includes/cache.php:30) in /var/www/
   vhosts/domain.com/httpdocs/wp-content/plugins/memcached/object-cache.php on line
   19
 * Please, HELP ))
 *  [lilmofo](https://wordpress.org/support/users/lilmofo/)
 * (@lilmofo)
 * [5 years, 4 months ago](https://wordpress.org/support/topic/fatal-error-cannot-redeclare-wp_cache_add/#post-13980437)
 * This has been answered here [https://wordpress.org/support/topic/cannot-redeclare-wp_cache_add-2/](https://wordpress.org/support/topic/cannot-redeclare-wp_cache_add-2/)
 * copy the file to wp-content instead of activating it in the backend.
 *  [Andrews32](https://wordpress.org/support/users/andrews32/)
 * (@andrews32)
 * [5 years, 2 months ago](https://wordpress.org/support/topic/fatal-error-cannot-redeclare-wp_cache_add/#post-14263267)
 * Hello,
 * probably you should make the “copy the file to wp-content instead of activating
   it in the backend.” message more attractive (of red color, bold, etc…) I`ve just
   posted a one-star review… Going to delete it…
 *  [iceblink](https://wordpress.org/support/users/iceblink/)
 * (@iceblink)
 * [5 years ago](https://wordpress.org/support/topic/fatal-error-cannot-redeclare-wp_cache_add/#post-14510126)
 * Update: Copying object-cache.php /wp-content
    Running WP 5.7.2 on PHP 7.4 Perhaps
   this plugin doesn’t handle a non-standard CONTENT path?
 * Fatal error: Cannot redeclare wp_cache_add() (previously declared in xxx/docs/
   cms/wp-content/object-cache.php:19) in xxx/docs/cms/wp-content/plugins/memcached/
   object-cache.php on line 19

Viewing 4 replies - 1 through 4 (of 4 total)

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 * 4 replies
 * 5 participants
 * Last reply from: [iceblink](https://wordpress.org/support/users/iceblink/)
 * Last activity: [5 years ago](https://wordpress.org/support/topic/fatal-error-cannot-redeclare-wp_cache_add/#post-14510126)
 * Status: not resolved