Title: Warning: Cannot modify header information
Last modified: May 16, 2018

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# Warning: Cannot modify header information

 *  [Toengel](https://wordpress.org/support/users/toengel/)
 * (@toengel)
 * [8 years, 2 months ago](https://wordpress.org/support/topic/warning-cannot-modify-header-information-189/)
 * Hi,
 * I installed BBPress and activated it… when I’m registering a new forum user I
   get the following error message:
 * AMP Author Box settings
    Warning: Cannot modify header information – headers 
   already sent by (output started at /………/wp-content/plugins/amp-author-box/amp-
   author-box.php:320) in /……./wp-includes/pluggable.php on line 1216
 * What can I do?
 * Toengel@Alex
 * The page I need help with: _[[log in](https://login.wordpress.org/?redirect_to=https%3A%2F%2Fwordpress.org%2Fsupport%2Ftopic%2Fwarning-cannot-modify-header-information-189%2F%3Foutput_format%3Dmd&locale=en_US)
   to see the link]_

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

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 * 0 replies
 * 1 participant
 * Last reply from: [Toengel](https://wordpress.org/support/users/toengel/)
 * Last activity: [8 years, 2 months ago](https://wordpress.org/support/topic/warning-cannot-modify-header-information-189/)
 * Status: not resolved