Title: Error Clearing Cache
Last modified: March 9, 2018

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# Error Clearing Cache

 *  [jgodfrey99](https://wordpress.org/support/users/jgodfrey99/)
 * (@jgodfrey99)
 * [8 years, 3 months ago](https://wordpress.org/support/topic/error-clearing-cache/)
 * I receive the following error when clicking any of the clear cache buttons. Rather
   annoying. It had worked fine until the last few days.
 * Fatal error: Uncaught exception ‘Exception’ with message ‘unknown engine ‘ in/
   home2/public_html/wp/wp-content/plugins/w3-total-cache/Cdnfsd_Core.php:48 Stack
   trace: #0 /home2/public_html/wp/wp-content/plugins/w3-total-cache/Cdnfsd_CacheFlush.
   php(199): W3TC\Cdnfsd_Core->get_engine() #1 [internal function]: W3TC\Cdnfsd_CacheFlush::
   w3tc_flush_execute_delayed_operations(Array) #2 /home2/public_html/wp/wp-includes/
   class-wp-hook.php(286): call_user_func_array(Array, Array) #3 /home2/public_html/
   wp/wp-includes/plugin.php(203): WP_Hook->apply_filters(Array, Array) #4 /home2/
   public_html/wp/wp-content/plugins/w3-total-cache/CacheFlush_Locally.php(253):
   apply_filters(‘w3tc_flush_exec…’, Array) #5 /home2/public_html/wp/wp-content/
   plugins/w3-total-cache/CacheFlush.php(188): W3TC\CacheFlush_Locally->execute_delayed_operations()#
   6 [internal function]: W3TC\CacheFlush->execute_delayed_operations() #7 /home2/
   public_html/wp/wp-includes/class-wp-hook.php(284): call_user_func in /home2/public_html/
   wp/wp-content/plugins/w3-total-cache/Cdnfsd_Core.php on line 48

Viewing 2 replies - 1 through 2 (of 2 total)

 *  Thread Starter [jgodfrey99](https://wordpress.org/support/users/jgodfrey99/)
 * (@jgodfrey99)
 * [8 years, 3 months ago](https://wordpress.org/support/topic/error-clearing-cache/#post-10055392)
 * I have uninstalled and re-installed the plugin without success.
 * _[ [Please do not bump.](https://wordpress.org/support/guidelines/#do-not-bump-posts)]_
 *  [ptblank](https://wordpress.org/support/users/ptblank/)
 * (@ptblank)
 * [8 years, 3 months ago](https://wordpress.org/support/topic/error-clearing-cache/#post-10079156)
 * Hey [@jgodfrey99](https://wordpress.org/support/users/jgodfrey99/),
 * There error is with the new FSD CDN Feature.
 * Take a look at [https://techjourney.net/fix-wordpress-w3-total-cache-w3tc-uncaught-exception-unknown-engine-500-fatal-error/](https://techjourney.net/fix-wordpress-w3-total-cache-w3tc-uncaught-exception-unknown-engine-500-fatal-error/)
 * Hope it helps.

Viewing 2 replies - 1 through 2 (of 2 total)

The topic ‘Error Clearing Cache’ is closed to new replies.

 * ![](https://ps.w.org/w3-total-cache/assets/icon-256x256.png?rev=1041806)
 * [W3 Total Cache](https://wordpress.org/plugins/w3-total-cache/)
 * [Frequently Asked Questions](https://wordpress.org/plugins/w3-total-cache/#faq)
 * [Support Threads](https://wordpress.org/support/plugin/w3-total-cache/)
 * [Active Topics](https://wordpress.org/support/plugin/w3-total-cache/active/)
 * [Unresolved Topics](https://wordpress.org/support/plugin/w3-total-cache/unresolved/)
 * [Reviews](https://wordpress.org/support/plugin/w3-total-cache/reviews/)

 * 2 replies
 * 2 participants
 * Last reply from: [ptblank](https://wordpress.org/support/users/ptblank/)
 * Last activity: [8 years, 3 months ago](https://wordpress.org/support/topic/error-clearing-cache/#post-10079156)
 * Status: not resolved