WordPress by Yoast version 220.127.116.11
Clean install of WordPress 3.5 and using Version 1.1 of Twenty Twelve. NO other plugins installed.
Downloaded WordPress SEO plugin from the Add-new Plugins Screen in WordPress. Activated Plugin and received the following error message.
Warning: Cannot modify header information - headers already sent by (output started at /home/proimpac/public_html/test/wp-admin/includes/template.php:1642) in /home/proimpac/public_html/test/wp-includes/pluggable.php on line 876
This is not the first time that I have received this error message but it has just started. So, I sent a message to host provider and here is what they replied:
Since this seems to be occuring on all new installations, I sent a message to my hosting service and they replied:
Your template sends the headers in the file + line
/home/proimpac/public_html/test/wp-admin/includes/template.php:1642 (second line in the putted code "<html") #### <!--[if IE 8]>
class="ie8 <?php echo $admin_html_class; ?>" <?php do_action('admin_xml_ns'); ?> <?php language_attributes(); ?>>
<![endif]--> <!--[if !(IE 8) ]><!--> <html xmlns="http://www.w3.org/1999/xhtml" class="<?php echo $admin_html_class; ?>" <?php do_action('admin_xml_ns'); ?> <?php language_attributes(); ?>>
Then the wordpress file
/home/proimpac/public_html/test/wp-includes/pluggable.php tries to send the headers again in line 876:
header("Location: $location", true, $status); ####
So, you have this error because your scripts try to send
the headers info twice. You can try to remove the lines from the first script
(can't say if your template will work correct after that, so I advise you to
save the copy of it) and check the web site. Or you can try with some default template.
Please get back to us if you need any further assistance
and let us know how else we can help.
At first, the host provider thought it had to do with Weaver Pro 1.2.7 but that is not the case since I'm using a clean install and the default Twenty Twelve Theme with no additional plugins!
The test site can be seen at http://www.test.proimpactllc.com
This just started, so something has changed recently...