Title: Topic Tag: cannot modify header | WordPress.org --- # Topic Tag: cannot modify header 1 [2](https://wordpress.org/support/topic-tag/cannot-modify-header/page/2/?output_format=md) [3](https://wordpress.org/support/topic-tag/cannot-modify-header/page/3/?output_format=md) [4](https://wordpress.org/support/topic-tag/cannot-modify-header/page/4/?output_format=md) [→](https://wordpress.org/support/topic-tag/cannot-modify-header/page/2/?output_format=md) - Topic - Participants - Replies - Last Post * - [Php issues after update.](https://wordpress.org/support/topic/php-issues-after-update/) - Started by: [FantomeLiberte](https://wordpress.org/support/users/fantomeliberte/) - 2 - 1 - [1 year, 6 months ago](https://wordpress.org/support/topic/php-issues-after-update/#post-18150666) - [Lina Asenova](https://wordpress.org/support/users/linaasenova/) * - [[MultiVendorX - WooCommerce Multivendor Marketplace AI Powered Solutions] PHP Warning: Cannot modify header information](https://wordpress.org/support/topic/php-warning-cannot-modify-header-information-23/) - Started by: [Aslam Khan Gouran](https://wordpress.org/support/users/aslamkhangouran/) - 2 - 3 - [3 years, 1 month ago](https://wordpress.org/support/topic/php-warning-cannot-modify-header-information-23/#post-16625335) - [MultiVendorX](https://wordpress.org/support/users/wcmp/) * - [[Comet Cache] PHP Warning: Cannot modify header](https://wordpress.org/support/topic/php-warning-cannot-modify-header-2/) - Started by: [Ram Freedman](https://wordpress.org/support/users/ramf/) - 1 - 0 - [4 years ago](https://wordpress.org/support/topic/php-warning-cannot-modify-header-2/) - [Ram Freedman](https://wordpress.org/support/users/ramf/) * - [Error when trying to access Admin Panel](https://wordpress.org/support/topic/error-when-trying-to-access-admin-panel-2/) - Started by: [sditmars1](https://wordpress.org/support/users/sditmars1/) - 2 - 1 - [5 years, 5 months ago](https://wordpress.org/support/topic/error-when-trying-to-access-admin-panel-2/#post-13814507) - [t-p](https://wordpress.org/support/users/t-p/) * - [[Multi-column Tag Map] arning: Cannot modify header information when editing a page](https://wordpress.org/support/topic/arning-cannot-modify-header-information-when-editing-a-page/) - Started by: [georgeL13](https://wordpress.org/support/users/georgel13/) - 2 - 7 - [5 years, 7 months ago](https://wordpress.org/support/topic/arning-cannot-modify-header-information-when-editing-a-page/#post-13524959) - [georgeL13](https://wordpress.org/support/users/georgel13/) * - [[WooCommerce] Error.Cannot modify header information](https://wordpress.org/support/topic/error-cannot-modify-header-information-16/) - Started by: [ed777vs](https://wordpress.org/support/users/ed777vs/) - 2 - 2 - [5 years, 8 months ago](https://wordpress.org/support/topic/error-cannot-modify-header-information-16/#post-13473921) - [ed777vs](https://wordpress.org/support/users/ed777vs/) * - [Nonprofit Website Broken – Warning: Cannot Modify Header Information](https://wordpress.org/support/topic/nonprofit-website-broken-warning-cannot-modify-header-information/) - 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Started by: [sigdd](https://wordpress.org/support/users/sigdd/) - 2 - 3 - [9 years, 3 months ago](https://wordpress.org/support/topic/undefined-index-error-cannot-modify-header/#post-8731345) - [AlanP57](https://wordpress.org/support/users/alanp57/) * - [bugs since I upgraded to wordpress 4.6.1](https://wordpress.org/support/topic/bugs-since-i-upgraded-to-wordpress-4-6-1/) - Started by: [billron](https://wordpress.org/support/users/billron/) - 2 - 7 - [9 years, 6 months ago](https://wordpress.org/support/topic/bugs-since-i-upgraded-to-wordpress-4-6-1/#post-8402573) - [billron](https://wordpress.org/support/users/billron/) * - [Cannot modify header information when trying to post??](https://wordpress.org/support/topic/cannot-modify-header-information-when-trying-to-post/) - Started by: [mediaseth](https://wordpress.org/support/users/mediaseth/) - 3 - 10 - [9 years, 7 months ago](https://wordpress.org/support/topic/cannot-modify-header-information-when-trying-to-post/#post-8368231) - [mediaseth](https://wordpress.org/support/users/mediaseth/) * - 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3 - 6 - [10 years, 8 months ago](https://wordpress.org/support/topic/cant-log-in-to-admin-page-i-get-warning-messages-when-i-try-to/#post-6519892) - [Tapan Kumer Das](https://wordpress.org/support/users/tapan29bd/) *   1 [2](https://wordpress.org/support/topic-tag/cannot-modify-header/page/2/?output_format=md) [3](https://wordpress.org/support/topic-tag/cannot-modify-header/page/3/?output_format=md) [4](https://wordpress.org/support/topic-tag/cannot-modify-header/page/4/?output_format=md) [→](https://wordpress.org/support/topic-tag/cannot-modify-header/page/2/?output_format=md) ## Topics ### Topics with no replies ### Non-support topics ### Resolved topics ### Unresolved topics ### All topics ## Feeds * [RSS Recent Posts](https://wordpress.org/support/forums/feed/) * [RSS Recent Topics](https://wordpress.org/support/topics/feed/)