Title: PHP 8.0 multiple header errors
Last modified: February 12, 2023

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# PHP 8.0 multiple header errors

 *  [laclickchic](https://wordpress.org/support/users/laclickchic/)
 * (@laclickchic)
 * [3 years, 3 months ago](https://wordpress.org/support/topic/php-8-0-multiple-header-errors/)
 * Hi, just update to PHP 8.0 and I’m seeing the following errors on the dashboard
   page and website in admin, please can you help? I have tried deactivating theme
   and plugins. Theme is Ocean WP with Elementor.
 * **Warning**: Trying to access array offset on value of type null in **/homepages/
   35/d823589354/htdocs/website/wp-content/plugins/woocommerce/src/Admin/Features/
   Navigation/CoreMenu.php**on line **246**
 * **Warning**: Cannot modify header information – headers already sent by (output
   started at /homepages/35/d823589354/htdocs/website/wp-content/plugins/woocommerce/
   src/Admin/Features/Navigation/CoreMenu.php:246) in **/homepages/35/d823589354/
   htdocs/website/wp-admin/includes/misc.php** on line **1416**
 * **Warning**: Cannot modify header information – headers already sent by (output
   started at /homepages/35/d823589354/htdocs/website/wp-content/plugins/woocommerce/
   src/Admin/Features/Navigation/CoreMenu.php:246) in **/homepages/35/d823589354/
   htdocs/website/wp-includes/functions.php** on line **6865**
 * **Warning**: Cannot modify header information – headers already sent by (output
   started at /homepages/35/d823589354/htdocs/website/wp-content/plugins/woocommerce/
   src/Admin/Features/Navigation/CoreMenu.php:246) in **/homepages/35/d823589354/
   htdocs/website/wp-includes/pluggable.php** on line **1416**
 * **Warning**: Cannot modify header information – headers already sent by (output
   started at /homepages/35/d823589354/htdocs/website/wp-content/plugins/woocommerce/
   src/Admin/Features/Navigation/CoreMenu.php:246) in **/homepages/35/d823589354/
   htdocs/website/wp-includes/pluggable.php** on line **1419**
 * Many Thanks
    -  This topic was modified 3 years, 3 months ago by [Steven Stern (sterndata)](https://wordpress.org/support/users/sterndata/).
      Reason: fixed url
 * The page I need help with: _[[log in](https://login.wordpress.org/?redirect_to=https%3A%2F%2Fwordpress.org%2Fsupport%2Ftopic%2Fphp-8-0-multiple-header-errors%2F%3Foutput_format%3Dmd&locale=en_US)
   to see the link]_

Viewing 2 replies - 1 through 2 (of 2 total)

 *  [mrtom414](https://wordpress.org/support/users/mrtom414/)
 * (@mrtom414)
 * [3 years, 3 months ago](https://wordpress.org/support/topic/php-8-0-multiple-header-errors/#post-16463699)
 * I would look at your navigation menu. I looks like it sending a null value for
   some reason. The error “cannot modify header” happen when the browser thinks 
   the header was sent. This is usually caused by an error that occurred earlier.
   The first error is complaining about a value being empty.
 *  Thread Starter [laclickchic](https://wordpress.org/support/users/laclickchic/)
 * (@laclickchic)
 * [3 years, 3 months ago](https://wordpress.org/support/topic/php-8-0-multiple-header-errors/#post-16463828)
 * Thanks for the help. I found one error but still getting the messages although
   it does disappear now when I deactivate woocommerce.

Viewing 2 replies - 1 through 2 (of 2 total)

The topic ‘PHP 8.0 multiple header errors’ is closed to new replies.

 * In: [Fixing WordPress](https://wordpress.org/support/forum/how-to-and-troubleshooting/)
 * 2 replies
 * 2 participants
 * Last reply from: [laclickchic](https://wordpress.org/support/users/laclickchic/)
 * Last activity: [3 years, 3 months ago](https://wordpress.org/support/topic/php-8-0-multiple-header-errors/#post-16463828)
 * Status: not resolved

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