Title: Cannot modify header information
Last modified: November 14, 2024

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# Cannot modify header information

 *  Resolved [jds2mpo](https://wordpress.org/support/users/jds2mpo/)
 * (@jds2mpo)
 * [1 year, 6 months ago](https://wordpress.org/support/topic/cannot-modify-header-information-203/)
 * We keep getting this warning Ilve redacted out web name: Cannot modify header
   information – headers already sent in /home/**{Redacted web name}/{Redacted web
   name}**/website/web/wp-content/plugins/nitropack/classes/Integration/Plugin/WCML.
   php

Viewing 1 replies (of 1 total)

 *  Plugin Support [phristanov](https://wordpress.org/support/users/phristanov/)
 * (@phristanov)
 * [1 year, 4 months ago](https://wordpress.org/support/topic/cannot-modify-header-information-203/#post-18262861)
 * Hey there,
 * Sorry for the late reply here! Hope you are safe and well.
 * According to our developers, there are few reasons for that warning, most notable
   of which are theme/plugin using “echo” and whitespaces before/after PHP opening/
   closing tags. Also, if echo, printf, var_dump or other output is used that could
   lead to such notification.
 * In detail the reasons are explained here: [https://stackoverflow.com/a/8028987](https://stackoverflow.com/a/8028987)
 * You can use the following articles with the help of your developer to find exact
   code that is responsible for the error:
 * [https://make.wordpress.org/support/handbook/appendix/breakfix-lessons/php-whitespace-headers-already-sent/](https://make.wordpress.org/support/handbook/appendix/breakfix-lessons/php-whitespace-headers-already-sent/)
 * [https://www.wp-tweaks.com/fix-headers-already-sent-errors-wordpress/](https://www.wp-tweaks.com/fix-headers-already-sent-errors-wordpress/)
 * As a last resort, you can also disable error reporting. If you are still experiencing
   this, please contact us at [support@nitropack.com](https://wordpress.org/support/topic/cannot-modify-header-information-203/support@nitropack.com?output_format=md)
 * Best,
   Plamen

Viewing 1 replies (of 1 total)

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

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 * 1 reply
 * 2 participants
 * Last reply from: [phristanov](https://wordpress.org/support/users/phristanov/)
 * Last activity: [1 year, 4 months ago](https://wordpress.org/support/topic/cannot-modify-header-information-203/#post-18262861)
 * Status: resolved