Title: Install Error
Last modified: December 2, 2022

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# Install Error

 *  Resolved [raywjohnson](https://wordpress.org/support/users/raywjohnson/)
 * (@raywjohnson)
 * [3 years, 6 months ago](https://wordpress.org/support/topic/install-error-78/)
 * When I tried to install, I get this error (extra path info removed).
 * Fatal error: Cannot redeclare wp_cache_add() (previously declared in ./wp-includes/
   cache.php:41) in ./wp-content/plugins/memcached/object-cache.php on line 19

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

 *  [mattwmc2001](https://wordpress.org/support/users/mattwmc2001/)
 * (@mattwmc2001)
 * [3 years, 6 months ago](https://wordpress.org/support/topic/install-error-78/#post-16263109)
 * I get the same error. Any fix?
 *  [mattwmc2001](https://wordpress.org/support/users/mattwmc2001/)
 * (@mattwmc2001)
 * [3 years, 6 months ago](https://wordpress.org/support/topic/install-error-78/#post-16263119)
 * Update: I think you don’t activate it as it’s a drop-in plugin.
 * See more here: [https://wordpress.org/support/topic/cannot-redeclare-wp_cache_add-2/](https://wordpress.org/support/topic/cannot-redeclare-wp_cache_add-2/)
 * Follow these instructions: [https://wordpress.org/plugins/memcached/#installation](https://wordpress.org/plugins/memcached/#installation)
 *  Thread Starter [raywjohnson](https://wordpress.org/support/users/raywjohnson/)
 * (@raywjohnson)
 * [3 years, 6 months ago](https://wordpress.org/support/topic/install-error-78/#post-16263363)
 * Excellent. Thank you!
    -  This reply was modified 3 years, 6 months ago by [raywjohnson](https://wordpress.org/support/users/raywjohnson/).
      Reason: Mark as resolved

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

The topic ‘Install Error’ is closed to new replies.

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 * 4 replies
 * 2 participants
 * Last reply from: [raywjohnson](https://wordpress.org/support/users/raywjohnson/)
 * Last activity: [3 years, 6 months ago](https://wordpress.org/support/topic/install-error-78/#post-16263363)
 * Status: resolved