Warning: require(conexion.php) [function.require]: failed to open stream: No such file or directory in C:\wamp\www\horarios\semanal\semanal.php on line 15

Fatal error: require() [function.require]: Failed opening required 'conexion.php' (include_path='.;C:\php5\pear') in C:\wamp\www\horarios\semanal\semanal.php on line 15