Hey There

I habe a problem, I uploaded the files from Concrete5 to my webspace. But when i try to install it and I call the index.php i get a Error Message:

Warning: require_once(Zend/Loader.php) [function.require-once]: failed to open stream: No such file or directory in /home/www/web578/html/Juniorenfirma/concrete/libraries/3rdparty/Zend/Translate.php on line 25

Fatal error: require_once() [function.require]: Failed opening required 'Zend/Loader.php' (include_path='.') in /home/www/web578/html/Juniorenfirma/concrete/libraries/3rdparty/Zend/Translate.php on line 25

Thank you for your Help!
You can whatch the site on:http://web578.login-98.hoststar.ch/Juniorenfirma...