Title: PHP Warning: Cannot modify header information
Last modified: August 21, 2016

---

# PHP Warning: Cannot modify header information

 *  [xzoom](https://wordpress.org/support/users/xzoom/)
 * (@xzoom)
 * [12 years, 4 months ago](https://wordpress.org/support/topic/php-warning-cannot-modify-header-information-7/)
 * In a wordpress multisite network, and since last plugin update, my log is full
   of the following php warning:
 *     ```
       PHP Warning:  Cannot modify header information - headers already sent by (output started at /path/wp-content/plugins/all-in-one-seo-pack/aioseop_class.php:1394) in /path/httpdocs/wp-includes/pluggable.php
       ```
   
 * Please, can you help me?
 * Thanks
 * [https://wordpress.org/plugins/all-in-one-seo-pack/](https://wordpress.org/plugins/all-in-one-seo-pack/)

The topic ‘PHP Warning: Cannot modify header information’ is closed to new replies.

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 * 0 replies
 * 1 participant
 * Last reply from: [xzoom](https://wordpress.org/support/users/xzoom/)
 * Last activity: [12 years, 4 months ago](https://wordpress.org/support/topic/php-warning-cannot-modify-header-information-7/)
 * Status: not resolved