Title: Fatal error
Last modified: July 21, 2022

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# Fatal error

 *  [18TommyBoy](https://wordpress.org/support/users/18tommyboy/)
 * (@18tommyboy)
 * [3 years, 9 months ago](https://wordpress.org/support/topic/fatal-error-4207/)
 * Good day, before have Redis, it work immediately. Yet want try the Memcached (
   testing is better or not), but fatal error:
 * Fatal error: Cannot redeclare wp_cache_add() (previously declared in /www/wwwroot/
   mysite.com/wp-includes/cache.php:41) in /www/wwwroot/mysite.com/wp-content/plugins/
   memcached/object-cache.php on line 19

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

 *  Plugin Contributor [Andrija Vučinić](https://wordpress.org/support/users/aidvu/)
 * (@aidvu)
 * [3 years, 9 months ago](https://wordpress.org/support/topic/fatal-error-4207/#post-15849397)
 * Hey there,
 * did you follow the Installation steps provided here: [https://wordpress.org/plugins/memcached/#installation](https://wordpress.org/plugins/memcached/#installation)?
   I’m guessing you just installed it like any other plugin, but it doesn’t work
   like that. 🙂
 *  Thread Starter [18TommyBoy](https://wordpress.org/support/users/18tommyboy/)
 * (@18tommyboy)
 * [3 years, 9 months ago](https://wordpress.org/support/topic/fatal-error-4207/#post-15849958)
 * Yes installed only. Omg, why need programming for it? Redis plugin only activated
   and goodbye.
    When no access to SSH so can’t activate the plugin?
 *  Plugin Contributor [Andrija Vučinić](https://wordpress.org/support/users/aidvu/)
 * (@aidvu)
 * [3 years, 9 months ago](https://wordpress.org/support/topic/fatal-error-4207/#post-15850156)
 * > When no access to SSH so can’t activate the plugin?
 * You can use FTP to copy the file, or a WP plugin like [https://wordpress.org/plugins/wp-file-manager/](https://wordpress.org/plugins/wp-file-manager/).
 * > Redis plugin only activated and goodbye.
 * Yeah, they overwrite the original file in code but we’d rather not. Also, most
   hosts provide these plugins as drop-ins for you. I’d say this one does need some
   dev knowledge (or at least understanding of what you’re doing).
    -  This reply was modified 3 years, 9 months ago by [Andrija Vučinić](https://wordpress.org/support/users/aidvu/).

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

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

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 * 3 replies
 * 2 participants
 * Last reply from: [Andrija Vučinić](https://wordpress.org/support/users/aidvu/)
 * Last activity: [3 years, 9 months ago](https://wordpress.org/support/topic/fatal-error-4207/#post-15850156)
 * Status: not resolved