header already sent...

[WPThemer]

hi all, it looks great..tried to test it and got following error..

WARNING: C:\xampp\htdocs\xampp\themename\wp-admin\admin-header.php:9 - Cannot modify header information - headers already sent call_user_func, WXR_Import_UI->dispatch, WXR_Import_UI->display_import_step, require('C:\xampp\htdocs\xampp\themename\wp-content\plugins\WordPress-Importer-master\templates\import.php'), WXR_Import_UI->render_header, require('C:\xampp\htdocs\xampp\themename\wp-content\plugins\WordPress-Importer-master\templates\header.php'), require_once('C:\xampp\htdocs\xampp\themename\wp-admin\admin-header.php'), header

[swissspidy]

Hey there

Am I right in assuming this happened after starting the import process via the admin UI?

[WPThemer]

Yes. that's right.

[rmccue]

This seems like a plugin or theme issue; where does the error say the original output is? (Should say something like "output started at ...")

[adambware]

WordPress 4.6.1 Theme = Twenty Sixteen Extra Plugins = Debug Bar

PHP Warnings:

PHP Warning:  Cannot modify header information - headers already sent in /nas/content/live/adamdev/wp-includes/option.php on line 823, referer: /wp-admin/admin.php?import=wordpress&step=1
PHP Warning:  Cannot modify header information - headers already sent in /nas/content/live/adamdev/wp-includes/option.php on line 824, referer: /wp-admin/admin.php?import=wordpress&step=1

These two lines are calls to setcookie() to "save and restore user interface settings"

Update: Debug Bar caught one Warning before these two.

WARNING: wp-admin/admin-header.php:9 - Cannot modify header information - headers already sent
call_user_func, WXR_Import_UI->dispatch, WXR_Import_UI->display_import_step, require('/plugins/WordPress-Importer-master/templates/import.php'), WXR_Import_UI->render_header, require('/plugins/WordPress-Importer-master/templates/header.php'), require_once('wp-admin/admin-header.php'), header