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

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# Warning: Cannot modify header information

 *  Resolved [leinster](https://wordpress.org/support/users/leinster/)
 * (@leinster)
 * [13 years, 7 months ago](https://wordpress.org/support/topic/warning-cannot-modify-header-information-90/)
 * Hi there,
 * I updated a plugin to its’ latest version and as a result am getting the error
   below on one of my web pages. Am using WP 3.4.2.
 * Would anyone be able to advise on how to get rid of this text which shows up 
   at the top of a page.
 * Warning: Cannot modify header information – headers already sent by (output started
   at /home/pow/public_html/wp-content/themes/theme1336/header.php:2) in /home/pow/
   public_html/wp-content/plugins/thecartpress/widgets/TaxonomyTreesPostTypeWidget.
   class.php on line 35

Viewing 1 replies (of 1 total)

 *  Thread Starter [leinster](https://wordpress.org/support/users/leinster/)
 * (@leinster)
 * [13 years, 7 months ago](https://wordpress.org/support/topic/warning-cannot-modify-header-information-90/#post-3070743)
 * In answering my own question after trying out many suggestions found on the web.
 * I had changed the category.php file a while ago to remove category archive text
   in the web page heading. I figured this may have had an effect.
 * Solution
 * Add `<?php ob_start(); ?>` to very top of file.
 * And add `<?php ob_end_flush(); ?>` to very end of file

Viewing 1 replies (of 1 total)

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

## Tags

 * [Cannot modify header information](https://wordpress.org/support/topic-tag/cannot-modify-header-information/)

 * In: [Fixing WordPress](https://wordpress.org/support/forum/how-to-and-troubleshooting/)
 * 1 reply
 * 1 participant
 * Last reply from: [leinster](https://wordpress.org/support/users/leinster/)
 * Last activity: [13 years, 7 months ago](https://wordpress.org/support/topic/warning-cannot-modify-header-information-90/#post-3070743)
 * Status: resolved

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