ocs2 has produced an error
  Message: WARNING: unlink(/data/conferences/cache/fc-pluginSettings-0-0-AcronPlugin.php): No such file or directory
  In file: /data/conferences/lib/pkp/classes/cache/FileCache.inc.php
  At line: 58
  Stacktrace: 
   File: (unknown) line (unknown)
     Function: PKPApplication->errorHandler(2, "unlink(/data/conferences/cache/fc-pluginSettings-0-0-AcronPlugin...", "/data/conferences/lib/pkp/classes/cache/FileCache.inc.php", 58, Array(0))
   File: /data/conferences/lib/pkp/classes/cache/FileCache.inc.php line 58
     Function: unlink("/data/conferences/cache/fc-pluginSettings-0-0-AcronPlugin.php")
   File: /data/conferences/lib/pkp/classes/cache/FileCache.inc.php line 79
     Function: FileCache->flush()
   File: /data/conferences/classes/plugins/PluginSettingsDAO.inc.php line 113
     Function: FileCache->setCache("crontab", Array(2))
   File: /data/conferences/classes/plugins/Plugin.inc.php line 65
     Function: PluginSettingsDAO->updateSetting(00, "AcronPlugin", "crontab", Array(2), "object")
   File: /data/conferences/plugins/generic/acron/AcronPlugin.inc.php line 144
     Function: Plugin->updateSetting(00, "crontab", Array(2), "object")
   File: /data/conferences/plugins/generic/acron/AcronPlugin.inc.php line 40
     Function: AcronPlugin->parseCrontab()
   File: /data/conferences/lib/pkp/classes/plugins/PluginRegistry.inc.php line 66
     Function: AcronPlugin->register("generic", "plugins/generic/acron")
   File: /data/conferences/lib/pkp/classes/plugins/PluginRegistry.inc.php line 119
     Function: PluginRegistry->register("generic", Object(AcronPlugin), "plugins/generic/acron")
   File: /data/conferences/lib/pkp/classes/core/Dispatcher.inc.php line 128
     Function: PluginRegistry->loadCategory("generic")
   File: /data/conferences/lib/pkp/classes/core/PKPApplication.inc.php line 170
     Function: Dispatcher->dispatch(Object(Request))
   File: /data/conferences/index.php line 65
     Function: PKPApplication->execute()
  Server info:
   OS: Linux
   PHP Version: 5.4.16
   Apache Version: Apache/2.4.6 (CentOS) PHP/5.4.16
   DB Driver: mysql
   DB server version: 10.1.31-MariaDB<br/>