Title: [Plugin: W3 Total Cache] Array to string conversion notices
Last modified: August 20, 2016

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# [Plugin: W3 Total Cache] Array to string conversion notices

 *  [vugluskra](https://wordpress.org/support/users/vugluskra/)
 * (@vugluskra)
 * [14 years, 11 months ago](https://wordpress.org/support/topic/plugin-w3-total-cache-array-to-string-conversion-notices/)
 * Please do anything with annoying PHP notices while creating static pages:
    Array
   to string conversion in \\wp-content\\plugins\\w3-total-cache\\lib\\W3\\Cache.
   php on line 52 Page Cache Method: Disk (enhanced).
 * [http://wordpress.org/extend/plugins/w3-total-cache/](http://wordpress.org/extend/plugins/w3-total-cache/)

Viewing 8 replies - 1 through 8 (of 8 total)

 *  [KimJCastleberry](https://wordpress.org/support/users/kimjcastleberry/)
 * (@kimjcastleberry)
 * [14 years, 11 months ago](https://wordpress.org/support/topic/plugin-w3-total-cache-array-to-string-conversion-notices/#post-2145590)
 * /wp-content/plugins/w3-total-cache/lib/W3/Cache.php on line 52
 * Similar error seen here. WP 3.2 RC4
 *  [KimJCastleberry](https://wordpress.org/support/users/kimjcastleberry/)
 * (@kimjcastleberry)
 * [14 years, 11 months ago](https://wordpress.org/support/topic/plugin-w3-total-cache-array-to-string-conversion-notices/#post-2145591)
 * it doesn’t seem to like this bit of code:
 * function &instance($engine, $config = array()) {
    static $instances = array();
 *  $instance_key = sprintf(‘%s_%s’, $engine, md5(implode(”, $config)));
 *  if (!isset($instances[$instance_key])) {
    switch ($engine) { case W3TC_CACHE_MEMCACHED:
   require_once W3TC_LIB_W3_DIR . ‘/Cache/Memcached.php’; $instances[$instance_key]
   = & ne
 *  Plugin Contributor [Frederick Townes](https://wordpress.org/support/users/fredericktownes/)
 * (@fredericktownes)
 * [14 years, 10 months ago](https://wordpress.org/support/topic/plugin-w3-total-cache-array-to-string-conversion-notices/#post-2145632)
 * Are people still having issues with this in the latest release?
 *  Thread Starter [vugluskra](https://wordpress.org/support/users/vugluskra/)
 * (@vugluskra)
 * [14 years, 10 months ago](https://wordpress.org/support/topic/plugin-w3-total-cache-array-to-string-conversion-notices/#post-2145634)
 * WP 3.2.1 / TC 0.9.2.3
 *     ```
       [Wed Jul 20 14:04:00 2011] [error] PHP Notice:  Array to string conversion in Cache.php on line 52, referer: /admin.php?page=w3tc_general
       [Wed Jul 20 14:04:29 2011] [error] PHP Notice:  Array to string conversion in Minify.php on line 796, referer: /wp-login.php?loggedout=true
       [Wed Jul 20 14:04:45 2011] [error] PHP Notice:  Array to string conversion in Cache.php on line 52, referer: /
       ```
   
 *  [Oliver Krautscheid (oliversk)](https://wordpress.org/support/users/soliver/)
 * (@soliver)
 * [14 years, 10 months ago](https://wordpress.org/support/topic/plugin-w3-total-cache-array-to-string-conversion-notices/#post-2145635)
 * Installed latest version today. Getting same error .. Is this a critical error?
 * PHP Notice: Array to string conversion in /public_html/wp-content/plugins/w3-
   total-cache/lib/W3/Cache.php on line 52
 * Also I wanted to let you know that sometimes it is still using the ?p=xxx codes
   and fails to rewrite to the correct URL – I believe it only happens when I am
   logged in but I need to do further testing.
 * Last, but not least I would like to ask where you store the index.html for the
   index page (blog homepage!) .. I can’t find it in w3tc/pgcache/..
 *  Plugin Contributor [Frederick Townes](https://wordpress.org/support/users/fredericktownes/)
 * (@fredericktownes)
 * [14 years, 8 months ago](https://wordpress.org/support/topic/plugin-w3-total-cache-array-to-string-conversion-notices/#post-2145654)
 * Are you still having this issue with 0.9.2.4?
 *  [hedgehogsbottom](https://wordpress.org/support/users/hedgehogsbottom/)
 * (@hedgehogsbottom)
 * [14 years, 4 months ago](https://wordpress.org/support/topic/plugin-w3-total-cache-array-to-string-conversion-notices/#post-2145689)
 * Yes, I’m using 0.9.2.4 and am getting this error. Specifically:-
 * [26-Jan-2012 11:05:10] PHP Notice: Array to string conversion in /home/sites/
   wordpress-mu/web/wp-content/plugins/w3-total-cache/lib/W3/Minify.php on line 
   810
    [26-Jan-2012 11:05:10] PHP Notice: Array to string conversion in /home/sites/
   wordpress-mu/web/wp-content/plugins/w3-total-cache/lib/W3/Minify.php on line 
   810 [26-Jan-2012 14:13:53] PHP Notice: Array to string conversion in /home/sites/
   wordpress-mu/web/wp-content/plugins/w3-total-cache/lib/W3/Minify.php on line 
   810 [26-Jan-2012 14:13:53] PHP Notice: Array to string conversion in /home/sites/
   wordpress-mu/web/wp-content/plugins/w3-total-cache/lib/W3/Minify.php on line 
   810
 * etc.
 * The function called is
    function _generate_id($sources, $type),
 * the line is:-
    $id = substr(md5(implode(”, $values)), 0, 6);
 * I have the JS and CSS minifiers set to manual (so that I can non-block load the
   Javascript for example).
 * Would it be helpful to debug the values for $sources and $type?
 * I’m quite comfy debugging and analysing PHP and Linux matters, so if there’s 
   something you (Frederick) would like me to try out and report upon I’d be happy
   to try and report back.
 * All the best,
    Hedgehog.
 *  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-array-to-string-conversion-notices/#post-2145692)
 * Thanks, this is fixed in the next release.

Viewing 8 replies - 1 through 8 (of 8 total)

The topic ‘[Plugin: W3 Total Cache] Array to string conversion notices’ 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/)
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 * 8 replies
 * 5 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-array-to-string-conversion-notices/#post-2145692)
 * Status: not resolved