Title: Cannot modify header information Last modified: February 2, 2020 --- # Cannot modify header information * Resolved [maxi07](https://wordpress.org/support/users/maxi07/) * (@maxi07) * [6 years, 4 months ago](https://wordpress.org/support/topic/cannot-modify-header-information-157/) * Hi there, when trying to save a page built with WPBakery with an Extensive VC Element inside, WordPress throws me the following error: * ``` Notice: Undefined index: evc_client_image in /homepages/8/d814731425/htdocs/clickandbuilds/Drivelist/wp-content/plugins/extensive-vc-addon/lib/framework/framework-meta-boxes.php on line 123 Notice: Undefined index: evc_client_hover_image in /homepages/8/d814731425/htdocs/clickandbuilds/Drivelist/wp-content/plugins/extensive-vc-addon/lib/framework/framework-meta-boxes.php on line 123 Notice: Undefined index: evc_client_link in /homepages/8/d814731425/htdocs/clickandbuilds/Drivelist/wp-content/plugins/extensive-vc-addon/lib/framework/framework-meta-boxes.php on line 123 Notice: Undefined index: evc_testimonial_text in /homepages/8/d814731425/htdocs/clickandbuilds/Drivelist/wp-content/plugins/extensive-vc-addon/lib/framework/framework-meta-boxes.php on line 123 Notice: Undefined index: evc_testimonial_author in /homepages/8/d814731425/htdocs/clickandbuilds/Drivelist/wp-content/plugins/extensive-vc-addon/lib/framework/framework-meta-boxes.php on line 123 Notice: Undefined index: evc_testimonial_position in /homepages/8/d814731425/htdocs/clickandbuilds/Drivelist/wp-content/plugins/extensive-vc-addon/lib/framework/framework-meta-boxes.php on line 123 Warning: Cannot modify header information - headers already sent by (output started at /homepages/8/d814731425/htdocs/clickandbuilds/Drivelist/wp-content/plugins/extensive-vc-addon/lib/framework/framework-meta-boxes.php:123) in /homepages/8/d814731425/htdocs/clickandbuilds/Drivelist/wp-admin/post.php on line 223 Warning: Cannot modify header information - headers already sent by (output started at /homepages/8/d814731425/htdocs/clickandbuilds/Drivelist/wp-content/plugins/extensive-vc-addon/lib/framework/framework-meta-boxes.php:123) in /homepages/8/d814731425/htdocs/clickandbuilds/Drivelist/wp-includes/pluggable.php on line 1265 Warning: Cannot modify header information - headers already sent by (output started at /homepages/8/d814731425/htdocs/clickandbuilds/Drivelist/wp-content/plugins/extensive-vc-addon/lib/framework/framework-meta-boxes.php:123) in /homepages/8/d814731425/htdocs/clickandbuilds/Drivelist/wp-includes/pluggable.php on line 1268 ``` * The website actually updates but the error persists. * Used plugins: 301 Redirects 2.45 All In One SEO Pack 3.3.4 Coming Soon Page, Under Construction & Maintenance Mode by SeedProd 5.1.0 Extensive VC Addons 1.8 Health Check & Troubleshooting 1.4.2 PayPal Donation 1.2.9 Server IP & Memory Usage Display 2.1.0 Simple Download Monitor 3.8.3 Slider Revolution 6.1.7 Smush 3.4.2 TheGem Theme Elements 4.2.0 UpdraftPlus – Backup/Restore 1.16.21 Wordpress Page Widgets 3.9 WPBakery Page Builder 6.1 * When deactivating the Extensive VC plugin, the error goes away. Has anybody else been running into a similar issue? * The page I need help with: _[[log in](https://login.wordpress.org/?redirect_to=https%3A%2F%2Fwordpress.org%2Fsupport%2Ftopic%2Fcannot-modify-header-information-157%2F%3Foutput_format%3Dmd&locale=en_US) to see the link]_ Viewing 4 replies - 1 through 4 (of 4 total) * Thread Starter [maxi07](https://wordpress.org/support/users/maxi07/) * (@maxi07) * [6 years, 4 months ago](https://wordpress.org/support/topic/cannot-modify-header-information-157/#post-12399182) * In addition, I think this error occurred after I started modifying my meta-descriptions and keywords for the website. * Plugin Author [Nenad Obradovic](https://wordpress.org/support/users/nenad-obradovic/) * (@nenad-obradovic) * [6 years, 4 months ago](https://wordpress.org/support/topic/cannot-modify-header-information-157/#post-12422189) * Hi maxi07, * That errors might be in relation will low server resource or some conflict between plugins, plugin – theme etc. * Did you try to deactivate other plugins one by one and to check your site again? * Could you provide me a temporary WordPress admin access to inspect that issue closer? You can send me access to [support@wprealize.com](https://wordpress.org/support/topic/cannot-modify-header-information-157/support@wprealize.com?output_format=md) and url to page where you have that issue * Best regards, Nenad * Thread Starter [maxi07](https://wordpress.org/support/users/maxi07/) * (@maxi07) * [6 years, 3 months ago](https://wordpress.org/support/topic/cannot-modify-header-information-157/#post-12435917) * So after the very appreciated help of the developer, changing the following fixed the issue. Search for the file * > extensive-vc-addon/lib/framework/framework-meta-boxes.php open this file * and change the following * ``` $post_types = apply_filters( 'extensive_vc_filter_allowed_post_types_meta_boxes', array( 'post', 'page' ) ); ``` * to this one * ``` $post_types = apply_filters( 'extensive_vc_filter_allowed_post_types_meta_boxes', array() ); ``` * Thanks a lot! * Plugin Author [Nenad Obradovic](https://wordpress.org/support/users/nenad-obradovic/) * (@nenad-obradovic) * [6 years, 3 months ago](https://wordpress.org/support/topic/cannot-modify-header-information-157/#post-12436031) * Hi Max, * You are welcome 😉 * Best regards, Nenad Viewing 4 replies - 1 through 4 (of 4 total) The topic ‘Cannot modify header information’ is closed to new replies. * ![](https://s.w.org/plugins/geopattern-icon/extensive-vc-addon_9b9998.svg) * [Extensive VC Addons for WPBakery page builder](https://wordpress.org/plugins/extensive-vc-addon/) * [Frequently Asked Questions](https://wordpress.org/plugins/extensive-vc-addon/#faq) * [Support Threads](https://wordpress.org/support/plugin/extensive-vc-addon/) * [Active Topics](https://wordpress.org/support/plugin/extensive-vc-addon/active/) * [Unresolved Topics](https://wordpress.org/support/plugin/extensive-vc-addon/unresolved/) * [Reviews](https://wordpress.org/support/plugin/extensive-vc-addon/reviews/) ## Tags * [header](https://wordpress.org/support/topic-tag/header/) * [Modify](https://wordpress.org/support/topic-tag/modify/) * [php-error](https://wordpress.org/support/topic-tag/php-error/) * 4 replies * 2 participants * Last reply from: [Nenad Obradovic](https://wordpress.org/support/users/nenad-obradovic/) * Last activity: [6 years, 3 months ago](https://wordpress.org/support/topic/cannot-modify-header-information-157/#post-12436031) * Status: resolved