Title: PHP errors when Debug enabled
Last modified: August 22, 2016

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# PHP errors when Debug enabled

 *  [buzzworkers](https://wordpress.org/support/users/buzzworkers/)
 * (@buzzworkers)
 * [11 years, 9 months ago](https://wordpress.org/support/topic/php-errors-when-debug-enabled-1/)
 * Warning: Cannot modify header information – headers already sent by (output started
   at /home//wp-content/plugins/rebelmouse-widget/rebelmouse-admin.php:396) in /
   home//wp-content/plugins/participants-database/classes/WP_Session.class.php on
   line 123
 * i see this on the backend/fronted when debug enabled
    latest version of wordpress
   + Avada + WPML
 * [https://wordpress.org/plugins/participants-database/](https://wordpress.org/plugins/participants-database/)

Viewing 5 replies - 1 through 5 (of 5 total)

 *  Plugin Author [Roland Barker](https://wordpress.org/support/users/xnau/)
 * (@xnau)
 * [11 years, 9 months ago](https://wordpress.org/support/topic/php-errors-when-debug-enabled-1/#post-5236840)
 * Yeah, this is avoidable if you put `define('WP_DEBUG_DISPLAY', false);` in your
   config file. This keeps the warnings from getting printed, and preempting the
   normal headers.
 * It’s best to use an error log when debugging anyway.
 *  [neverminder](https://wordpress.org/support/users/neverminder/)
 * (@neverminder)
 * [11 years, 6 months ago](https://wordpress.org/support/topic/php-errors-when-debug-enabled-1/#post-5237000)
 * That’s not a solution “per say”, it’s just a way not to see the warning anymore.
   But the problem is still there and it conflicts badly with WPML. So… any idea?
 *  Plugin Author [Roland Barker](https://wordpress.org/support/users/xnau/)
 * (@xnau)
 * [11 years, 6 months ago](https://wordpress.org/support/topic/php-errors-when-debug-enabled-1/#post-5237001)
 * Whatever the “rebelmouse” plugin is doing seems to be causing the problem in 
   the first place. Try it with that plugin deactivated.
 *  [neverminder](https://wordpress.org/support/users/neverminder/)
 * (@neverminder)
 * [11 years, 6 months ago](https://wordpress.org/support/topic/php-errors-when-debug-enabled-1/#post-5237002)
 * It’s not just the rebelmouse plugin:
 * `Warning: Cannot modify header information - headers already sent by (output 
   started at /wp-includes/functions.php:3092) in /wp-content/plugins/participants-
   database/classes/WP_Session.class.php on line 123`
 *  Plugin Author [Roland Barker](https://wordpress.org/support/users/xnau/)
 * (@xnau)
 * [11 years, 6 months ago](https://wordpress.org/support/topic/php-errors-when-debug-enabled-1/#post-5237003)
 * OK, I’ll need to chase this down and add a bug report for this. Thanks for the
   report.
 * For the moment, I don’t know how to fix this, although there is some possibility
   changing the “Use PHP Sessions” setting under the advanced tab of the plugin 
   settings might fix it.

Viewing 5 replies - 1 through 5 (of 5 total)

The topic ‘PHP errors when Debug enabled’ is closed to new replies.

 * ![](https://ps.w.org/participants-database/assets/icon-256x256.jpg?rev=1389807)
 * [Participants Database](https://wordpress.org/plugins/participants-database/)
 * [Frequently Asked Questions](https://wordpress.org/plugins/participants-database/#faq)
 * [Support Threads](https://wordpress.org/support/plugin/participants-database/)
 * [Active Topics](https://wordpress.org/support/plugin/participants-database/active/)
 * [Unresolved Topics](https://wordpress.org/support/plugin/participants-database/unresolved/)
 * [Reviews](https://wordpress.org/support/plugin/participants-database/reviews/)

 * 5 replies
 * 3 participants
 * Last reply from: [Roland Barker](https://wordpress.org/support/users/xnau/)
 * Last activity: [11 years, 6 months ago](https://wordpress.org/support/topic/php-errors-when-debug-enabled-1/#post-5237003)
 * Status: not resolved