Title: WARNING ERROR
Last modified: August 21, 2016

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# WARNING ERROR

 *  Resolved [laraurkiola](https://wordpress.org/support/users/laraurkiola/)
 * (@laraurkiola)
 * [12 years, 10 months ago](https://wordpress.org/support/topic/warning-error-9/)
 * I’m trying to use this plugin but I have several problems:
    When the plugin is
   activated, everytime I’ve made a change this error appears: **Warning**: Cannot
   modify header information – headers already sent by (output started at **/homepages/
   46/d481334801/htdocs/wp-content/plugins/lordlinus-class-booking/lordlinus-class-
   booking.php:39) in/homepages/46/d481334801/htdocs/wp-includes/pluggable.php **
   on line **876**.
 * In other hand, the shortcode [BOOK_MY_CLASS] doesn’t work, even if the comments
   in the page are off.
 * Could you help me, please? I’ll really appreciate that. Thanks.
 * [http://wordpress.org/plugins/lordlinus-class-booking/](http://wordpress.org/plugins/lordlinus-class-booking/)

Viewing 1 replies (of 1 total)

 *  Plugin Author [Rohitashv Singhal](https://wordpress.org/support/users/lordlinus/)
 * (@lordlinus)
 * [12 years, 10 months ago](https://wordpress.org/support/topic/warning-error-9/#post-4018253)
 * Hello laraurkiola,
 * I have seen the problem, That problem is not from plugin side.That is the problem
   from theme side, Please send me the name of theme which you have applied on your
   wordpress, so that we can figure out the problem
 * Thanks

Viewing 1 replies (of 1 total)

The topic ‘WARNING ERROR’ is closed to new replies.

 * ![](https://s.w.org/plugins/geopattern-icon/lordlinus-class-booking.svg)
 * [Class Booking Plugin](https://wordpress.org/plugins/lordlinus-class-booking/)
 * [Support Threads](https://wordpress.org/support/plugin/lordlinus-class-booking/)
 * [Active Topics](https://wordpress.org/support/plugin/lordlinus-class-booking/active/)
 * [Unresolved Topics](https://wordpress.org/support/plugin/lordlinus-class-booking/unresolved/)
 * [Reviews](https://wordpress.org/support/plugin/lordlinus-class-booking/reviews/)

 * 1 reply
 * 2 participants
 * Last reply from: [Rohitashv Singhal](https://wordpress.org/support/users/lordlinus/)
 * Last activity: [12 years, 10 months ago](https://wordpress.org/support/topic/warning-error-9/#post-4018253)
 * Status: resolved