PHP Version OK PHP 5.3.3-7+squeeze28
Writable Webspace Main Folder OK /home/www/web61/html/1hilfe-ilias
Can Create Folders in Webspace Main Folder OK
Cookies Enabled FAILED Cookies are disabled. Cookies are required to use ILIAS.
DOM Support OK
XSL Support FAILED Please enable XSL support in your PHP installation, see PHP Documentation.
GD Support OK
PHP Memory Limit Setting (php.ini) OK 128M. We recommend a value of 80M or more.

Some basic requirements are not met by your installation. You can get further information at the ILIAS site.