Title: Cannot modify header information
Last modified: August 20, 2016

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# Cannot modify header information

 *  [sophie.operationnelle](https://wordpress.org/support/users/sophieoperationnelle/)
 * (@sophieoperationnelle)
 * [14 years, 1 month ago](https://wordpress.org/support/topic/cannot-modify-header-information-55/)
 * I am working on the back office, so we can easily edit an article. Somehow each
   time I save the modifications, it send me to blank [http://nnnnnnnn/wp-admin/post.php](http://nnnnnnnn/wp-admin/post.php)
   with this error.
 * > Warning: Cannot modify header information – headers already sent by (output
   > started at /homepages/nnnn/hhh/mmmm/ddd/wp-content/themes/ssss/) in /homepages/
   > nn/nnnnn/nnnn/nnnn/wp-includes/pluggable.php on line 866
 * Is it a problem with my theme/template, or is this wordpress having a problem.
   I’ve started over 3 times, and the last time, I hardly changed anything in the
   code, and still get this message.
 * If anyone had this problem before, please notify me.

Viewing 1 replies (of 1 total)

 *  [esmi](https://wordpress.org/support/users/esmi/)
 * (@esmi)
 * [14 years, 1 month ago](https://wordpress.org/support/topic/cannot-modify-header-information-55/#post-2723902)
 * Have you tried:
 * – deactivating **all** plugins to see if this resolves the problem. If this works,
   re-activate the plugins one by one until you find the problematic plugin(s).
 * – switching to the Twenty Eleven theme to rule out any theme-specific problems.
 * – [resetting the plugins folder](http://codex.wordpress.org/FAQ_Troubleshooting#How_to_deactivate_all_plugins_when_not_able_to_access_the_administrative_menus.3F)
   by FTP or PhpMyAdmin. Sometimes, an apparently inactive plugin can still cause
   problems.
 * – re-uploading the wp-admin and wp-includes folders from a **fresh** download
   of WordPress 3.3.1.

Viewing 1 replies (of 1 total)

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

## Tags

 * [header](https://wordpress.org/support/topic-tag/header/)
 * [pluggable](https://wordpress.org/support/topic-tag/pluggable/)

 * In: [Fixing WordPress](https://wordpress.org/support/forum/how-to-and-troubleshooting/)
 * 1 reply
 * 2 participants
 * Last reply from: [esmi](https://wordpress.org/support/users/esmi/)
 * Last activity: [14 years, 1 month ago](https://wordpress.org/support/topic/cannot-modify-header-information-55/#post-2723902)
 * Status: not resolved

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