« MODx Parse Error »

MODx encountered the following error while attempting to parse the requested resource:
« PHP Parse Error »
 
PHP error debug
  Error: file(assets/cache/docid_16.pageCache.php): failed to open stream: Permission denied 
  Error type/ Nr.: Warning - 2 
  File: /homepages/23/d399786253/htdocs/raumerschaffen.de/manager/includes/document.parser.class.inc.php 
  Line: 413 
  Line 413 source: $flContent= implode("", file($cacheFile));  
 
Parser timing
  MySQL: 0.0027 s(0 Requests)
  PHP: 0.0143 s 
  Total: 0.0170 s