Title: PHP Error, undefined function?
Last modified: August 20, 2016

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# PHP Error, undefined function?

 *  [rykios](https://wordpress.org/support/users/rykios/)
 * (@rykios)
 * [13 years, 7 months ago](https://wordpress.org/support/topic/php-error-undefined-function/)
 * Have been using w3TC for long, never had a single problem. Most effective and
   COMPLETE caching plugin, by far 🙂
    After a recent move to a new server, i noticed
   error log in public_html, full with lines like this one: `[21-Oct-2012 06:10:
   54 UTC] PHP Fatal error: Call to undefined function w3_url_format() in /home/
   radicio/public_html/wp-content/plugins/w3-total-cache/lib/W3/Plugin/PgCacheAdmin.
   php on line 213` All look like this one, only time stamps change.
 * Any ideas?
 * [http://wordpress.org/extend/plugins/w3-total-cache/](http://wordpress.org/extend/plugins/w3-total-cache/)

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

 *  Thread Starter [rykios](https://wordpress.org/support/users/rykios/)
 * (@rykios)
 * [13 years, 7 months ago](https://wordpress.org/support/topic/php-error-undefined-function/#post-3133346)
 * I m not a php expert, but it looks like function w3_url_format is indeed undefined.
   At least not in functions/http.php
    Looks like a bug indeed.
 * Result: Preload not working (checked via FTP for new page folders written in 
   cache folder, and verified, only visited pages are cached)
 *  Thread Starter [rykios](https://wordpress.org/support/users/rykios/)
 * (@rykios)
 * [13 years, 7 months ago](https://wordpress.org/support/topic/php-error-undefined-function/#post-3133347)
 * ok it is a bug, that function is defined in another file (url.php)
 * To fix:
    Edit file /wp-content/plugins/w3-total-cache/lib/W3/Plugin/PgCacheAdmin.
   php
 * Change line 210 to this:
    `require_once W3TC_INC_DIR . '/functions/url.php';`
 * Error, sorted. (Still cannot verify that there are pre-cache files generated,
   as it needs time)
 *  Plugin Contributor [Frederick Townes](https://wordpress.org/support/users/fredericktownes/)
 * (@fredericktownes)
 * [13 years, 3 months ago](https://wordpress.org/support/topic/php-error-undefined-function/#post-3133427)
 * This is fixed in the next release.

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

The topic ‘PHP Error, undefined function?’ is closed to new replies.

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## Tags

 * [W3TC](https://wordpress.org/support/topic-tag/w3tc/)

 * 3 replies
 * 2 participants
 * Last reply from: [Frederick Townes](https://wordpress.org/support/users/fredericktownes/)
 * Last activity: [13 years, 3 months ago](https://wordpress.org/support/topic/php-error-undefined-function/#post-3133427)
 * Status: not resolved