Title: Error, Cannot Modify Header Information
Last modified: August 22, 2016

---

# Error, Cannot Modify Header Information

 *  Resolved [mountainguy2](https://wordpress.org/support/users/mountainguy2/)
 * (@mountainguy2)
 * [11 years, 6 months ago](https://wordpress.org/support/topic/error-cannot-modify-header-information-10/)
 * Hi Pascal, a user I’m trying to whitelist in a blocked country is getting this
   message when he tries to view my website:
 * Warning: Cannot modify header information – headers already sent by (output started
   at /home/***/public_html/wp-content/themes/mytheme/header.php:3) in /home/****/
   public_html/wp-content/plugins/iq-block-country/libs/blockcountry-checks.php 
   on line 270
 * Any ideas what’s going on?
 * Thanks, MTN
 * [https://wordpress.org/plugins/iq-block-country/](https://wordpress.org/plugins/iq-block-country/)

Viewing 1 replies (of 1 total)

 *  Plugin Author [Pascal](https://wordpress.org/support/users/iqpascal/)
 * (@iqpascal)
 * [11 years, 6 months ago](https://wordpress.org/support/topic/error-cannot-modify-header-information-10/#post-5437773)
 * Hi,
 * You need to set the buffer option on the home tab. There probably is some plugin
   or perhaps your theme that already sends output before iQ Block Country can.
 * The output buffer however stops some plugins from working correctly (like nextgen
   gallery upload).

Viewing 1 replies (of 1 total)

The topic ‘Error, Cannot Modify Header Information’ is closed to new replies.

 * ![](https://ps.w.org/iq-block-country/assets/icon-128x128.png?rev=3136019)
 * [iQ Block Country](https://wordpress.org/plugins/iq-block-country/)
 * [Frequently Asked Questions](https://wordpress.org/plugins/iq-block-country/#faq)
 * [Support Threads](https://wordpress.org/support/plugin/iq-block-country/)
 * [Active Topics](https://wordpress.org/support/plugin/iq-block-country/active/)
 * [Unresolved Topics](https://wordpress.org/support/plugin/iq-block-country/unresolved/)
 * [Reviews](https://wordpress.org/support/plugin/iq-block-country/reviews/)

 * 1 reply
 * 2 participants
 * Last reply from: [Pascal](https://wordpress.org/support/users/iqpascal/)
 * Last activity: [11 years, 6 months ago](https://wordpress.org/support/topic/error-cannot-modify-header-information-10/#post-5437773)
 * Status: resolved