Title: Error in functions.php
Last modified: August 31, 2016

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# Error in functions.php

 *  [matnfneo](https://wordpress.org/support/users/matnfneo/)
 * (@matnfneo)
 * [10 years, 2 months ago](https://wordpress.org/support/topic/error-in-functionsphp-6/)
 * Hi, today when I was to login I saw the following error:
 * Warning: Parameter 1 to W3_Plugin_TotalCache::ob_callback() expected to be a 
   reference, value given in /www/matiasfumazoni/htdocs/wp-includes/functions.php
   on line 3464
 * That line show: “ob_end_flush();”
 * function wp_ob_end_flush_all() {
    $levels = ob_get_level(); for ($i=0; $i<$levels;
   $i++) ob_end_flush(); }
 * Which is the solution to this? Thanks!
 * [https://wordpress.org/plugins/w3-total-cache/](https://wordpress.org/plugins/w3-total-cache/)

Viewing 6 replies - 1 through 6 (of 6 total)

 *  [Scott Hartley](https://wordpress.org/support/users/destac/)
 * (@destac)
 * [10 years, 2 months ago](https://wordpress.org/support/topic/error-in-functionsphp-6/#post-7237337)
 * You should remove those lines because they are staying that the file type should
   be served with gzip. But w3tc is also saying to serve it with gzip.
 * Or you can disable gzip in the w3tc browser cache settings.
 *  Thread Starter [matnfneo](https://wordpress.org/support/users/matnfneo/)
 * (@matnfneo)
 * [10 years, 2 months ago](https://wordpress.org/support/topic/error-in-functionsphp-6/#post-7237346)
 * Hi Destac, thanks for the quiqly reply.
 * No, I tried deleting those lines and other error appears with wp_ob_end_flush_all
   in another file (/wp-includes/plugin.php). I also tried disabling gzip in w3tc,
   but the error persist.
 *  [Scott Hartley](https://wordpress.org/support/users/destac/)
 * (@destac)
 * [10 years, 2 months ago](https://wordpress.org/support/topic/error-in-functionsphp-6/#post-7237365)
 * You could try switching the page cache module to basic. But i think it’s the 
   case of a theme issue or one that is poorly designed.
 *  Thread Starter [matnfneo](https://wordpress.org/support/users/matnfneo/)
 * (@matnfneo)
 * [10 years, 2 months ago](https://wordpress.org/support/topic/error-in-functionsphp-6/#post-7237366)
 * These are the errors after deleting the lines that I post before:
 * Warning: call_user_func_array() expects parameter 1 to be a valid callback, function‘
   wp_ob_end_flush_all’ not found or invalid function name in /www/matiasfumazoni/
   htdocs/wp-includes/plugin.php on line 525
 * Warning: Parameter 1 to W3_Plugin_TotalCache::ob_callback() expected to be a 
   reference, value given in Unknown on line 0
 * And these are the lines involved:
 *  do {
    foreach ( (array) current($wp_filter[$tag]) as $the_ ) if ( !is_null($
   the_[‘function’]) ) call_user_func_array($the_[‘function’], array_slice($args,
   0, (int) $the_[‘accepted_args’]));
 *  } while ( next($wp_filter[$tag]) !== false );
 *  array_pop($wp_current_filter);
    }
 *  [Scott Hartley](https://wordpress.org/support/users/destac/)
 * (@destac)
 * [10 years, 2 months ago](https://wordpress.org/support/topic/error-in-functionsphp-6/#post-7237367)
 * Disable database, and object caching if you have them running.
 *  Thread Starter [matnfneo](https://wordpress.org/support/users/matnfneo/)
 * (@matnfneo)
 * [10 years, 2 months ago](https://wordpress.org/support/topic/error-in-functionsphp-6/#post-7237390)
 * Yes, those options were disabled.
 * I decided to uninstall W3TC, and install WPSC, and its working fine so far.
 * I wasn’t able to find a solution to my issue, so I opted for change the plugin.
 * Anyway, I still having a slow load page speed.

Viewing 6 replies - 1 through 6 (of 6 total)

The topic ‘Error in functions.php’ 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)
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 * 6 replies
 * 2 participants
 * Last reply from: [matnfneo](https://wordpress.org/support/users/matnfneo/)
 * Last activity: [10 years, 2 months ago](https://wordpress.org/support/topic/error-in-functionsphp-6/#post-7237390)
 * Status: not resolved