Title: [Plugin: W3 Total Cache] Fatal Error: undefined method stdClass::set_prefix()
Last modified: August 20, 2016

---

# [Plugin: W3 Total Cache] Fatal Error: undefined method stdClass::set_prefix()

 *  [RahulB](https://wordpress.org/support/users/rahulb/)
 * (@rahulb)
 * [14 years, 5 months ago](https://wordpress.org/support/topic/plugin-w3-total-cache-fata-error-undefined-method-stdclassset_prefix/)
 * We are using the latest version of W3TC with WP 3.0.5
    As soon as we enable W3TC,
   gives a fatal error.
 * Fatal error: Call to undefined method stdClass::set_prefix() in /home/mydomain/
   wp4/wp-includes/load.php on line 337
 * Even the admin gives an error. Need to delete files like advanced-cache.php, 
   db.php, slowly after deleting w3-total-cache folder from plugins directory.
    
   After deleting the files one after the other, I get the admin dashboard back.
 * Any thoughts on the way forward?
    -Rahul Baji
 * [http://wordpress.org/extend/plugins/w3-total-cache/](http://wordpress.org/extend/plugins/w3-total-cache/)

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

 *  [junsanchez](https://wordpress.org/support/users/junsanchez/)
 * (@junsanchez)
 * [14 years, 5 months ago](https://wordpress.org/support/topic/plugin-w3-total-cache-fata-error-undefined-method-stdclassset_prefix/#post-2463094)
 * I got the same problem, the same Fatal error report.
 * I’m using WP version 3.0.1
 * Any help on this problem will be greatly appreciated as I really want to use 
   W3TC.
 * Thanks in advance
 * Jun Sanchez
 *  Thread Starter [RahulB](https://wordpress.org/support/users/rahulb/)
 * (@rahulb)
 * [14 years, 4 months ago](https://wordpress.org/support/topic/plugin-w3-total-cache-fata-error-undefined-method-stdclassset_prefix/#post-2463224)
 * Instead of using the latest version of W3TC, I used a version previous to the
   latest. That worked.
 *  [Kraignos](https://wordpress.org/support/users/kraignos/)
 * (@kraignos)
 * [14 years, 4 months ago](https://wordpress.org/support/topic/plugin-w3-total-cache-fata-error-undefined-method-stdclassset_prefix/#post-2463225)
 * WP ——>**3.0.3**
    W3 Total -> **0.9.2.4**
 * Worked for me chmodding temporarily wp-content/ and wp-content/uploads/ to 777,
   as said in the install instructions.
 * Back and Front-end both work.
 * Beware that it overwrites your .htaccess file.
 *  Plugin Contributor [Frederick Townes](https://wordpress.org/support/users/fredericktownes/)
 * (@fredericktownes)
 * [14 years, 3 months ago](https://wordpress.org/support/topic/plugin-w3-total-cache-fata-error-undefined-method-stdclassset_prefix/#post-2463253)
 * Unfortunately there is upgrade problem between .3 and .4 version, you’ll need
   to make wp-content folder writeable prior to upgrading.

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

The topic ‘[Plugin: W3 Total Cache] Fatal Error: undefined method stdClass::set_prefix()’
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/)

 * 4 replies
 * 4 participants
 * Last reply from: [Frederick Townes](https://wordpress.org/support/users/fredericktownes/)
 * Last activity: [14 years, 3 months ago](https://wordpress.org/support/topic/plugin-w3-total-cache-fata-error-undefined-method-stdclassset_prefix/#post-2463253)
 * Status: not resolved