« MODx Parse Error »

MODx encountered the following error while attempting to parse the requested resource:
« PHP Parse Error »
 
PHP error debug
  Error: Cannot modify header information - headers already sent by (output started at /home/c/cg30377/public_html/index.php:11) 
  Error type/ Nr.: Warning - 2 
  File: /home/c/cg30377/public_html/manager/includes/document.parser.class.inc.php 
  Line: 514 
 
Parser timing
  MySQL: 0,0014 s(6 Requests)
  PHP: 0,0237 s 
  Total: 0,0251 s