Title: PHP Warning:  session_start(): Cannot send session cookie
Last modified: August 30, 2016

---

# PHP Warning: session_start(): Cannot send session cookie

 *  Resolved [webitman](https://wordpress.org/support/users/webitman/)
 * (@webitman)
 * [10 years, 11 months ago](https://wordpress.org/support/topic/php-warning-session_start-cannot-send-session-cookie/)
 * I had an issue with line 8 in includes/multisite.php
    The error.log file shows
   PHP Warning: session_start(): Cannot send session cookie – headers already sent
   in /public_html/wp-content/plugins/ad-blocking-detector/includes/multisite.php
   on line 8
 * Please correct this in further releases.
    Recommended way for versions of PHP
   >= 5.4.0 if (session_status() == PHP_SESSION_NONE) { session_start(); } Source:
   [http://www.php.net/manual/en/function.session-status.php](http://www.php.net/manual/en/function.session-status.php)
   For versions of PHP < 5.4.0
 * if(session_id() == ”) {
    session_start(); }
 * [https://wordpress.org/plugins/ad-blocking-detector/](https://wordpress.org/plugins/ad-blocking-detector/)

Viewing 1 replies (of 1 total)

 *  [John Morris](https://wordpress.org/support/users/jtmorris/)
 * (@jtmorris)
 * [10 years, 11 months ago](https://wordpress.org/support/topic/php-warning-session_start-cannot-send-session-cookie/#post-6303274)
 * Whoops! Sorry about that. I correctly deal with SESSIONs in other files, but 
   this slipped through.
 * The next plugin update I will release will get rid of this problem. It will also
   mean I can likely get rid of SESSIONs altogether in the future too.
 * It’s actually worse than just PHP 5.4/5.3 issues… sometimes WordPress (or other
   WordPress plugins) do very strange things to SESSIONs which cause all sorts of
   haywire problems. They’re very difficult to rely on.

Viewing 1 replies (of 1 total)

The topic ‘PHP Warning: session_start(): Cannot send session cookie’ is closed to
new replies.

 * ![](https://s.w.org/plugins/geopattern-icon/ad-blocking-detector_466992.svg)
 * [Ad Blocking Detector](https://wordpress.org/plugins/ad-blocking-detector/)
 * [Frequently Asked Questions](https://wordpress.org/plugins/ad-blocking-detector/#faq)
 * [Support Threads](https://wordpress.org/support/plugin/ad-blocking-detector/)
 * [Active Topics](https://wordpress.org/support/plugin/ad-blocking-detector/active/)
 * [Unresolved Topics](https://wordpress.org/support/plugin/ad-blocking-detector/unresolved/)
 * [Reviews](https://wordpress.org/support/plugin/ad-blocking-detector/reviews/)

## Tags

 * [cookie](https://wordpress.org/support/topic-tag/cookie/)
 * [session](https://wordpress.org/support/topic-tag/session/)
 * [session_start](https://wordpress.org/support/topic-tag/session_start/)
 * [warning](https://wordpress.org/support/topic-tag/warning/)

 * 1 reply
 * 2 participants
 * Last reply from: [John Morris](https://wordpress.org/support/users/jtmorris/)
 * Last activity: [10 years, 11 months ago](https://wordpress.org/support/topic/php-warning-session_start-cannot-send-session-cookie/#post-6303274)
 * Status: resolved