If you see this page, it means your sandbox is not correctly set up. Please see the README file in the sandbox root folder and if you can't figure out what is wrong, ask us on freenode irc #symfony-cmf or the mailinglist symfony-cmf-users@groups.google.com.
Detected the following problem: Hm. No clue what goes wrong. Maybe this is a real 404?
exception 'Symfony\Component\Routing\Exception\ResourceNotFoundException' with message 'None of the routers in the chain matched '/sitemap.xml'' in /var/www/domainedescolibris/vendor/cmf-routing/Symfony/Cmf/Component/Routing/ChainRouter.php:103 Stack trace: #0 /var/www/domainedescolibris/vendor/symfony/src/Symfony/Component/HttpKernel/EventListener/RouterListener.php(56): Symfony\Cmf\Component\Routing\ChainRouter->match('/sitemap.xml') #1 [internal function]: Symfony\Component\HttpKernel\EventListener\RouterListener->onKernelRequest(Object(Symfony\Component\HttpKernel\Event\GetResponseEvent)) #2 /var/www/domainedescolibris/vendor/symfony/src/Symfony/Component/EventDispatcher/EventDispatcher.php(164): call_user_func(Array, Object(Symfony\Component\HttpKernel\Event\GetResponseEvent)) #3 /var/www/domainedescolibris/vendor/symfony/src/Symfony/Component/EventDispatcher/EventDispatcher.php(53): Symfony\Component\EventDispatcher\EventDispatcher->doDispatch(Array, 'kernel.request', Object(Symfony\Component\HttpKernel\Event\GetResponseEvent)) #4 /var/www/domainedescolibris/vendor/symfony/src/Symfony/Component/EventDispatcher/ContainerAwareEventDispatcher.php(165): Symfony\Component\EventDispatcher\EventDispatcher->dispatch('kernel.request', Object(Symfony\Component\HttpKernel\Event\GetResponseEvent)) #5 /var/www/domainedescolibris/vendor/symfony/src/Symfony/Component/HttpKernel/HttpKernel.php(109): Symfony\Component\EventDispatcher\ContainerAwareEventDispatcher->dispatch('kernel.request', Object(Symfony\Component\HttpKernel\Event\GetResponseEvent)) #6 /var/www/domainedescolibris/vendor/symfony/src/Symfony/Component/HttpKernel/HttpKernel.php(72): Symfony\Component\HttpKernel\HttpKernel->handleRaw(Object(Symfony\Component\HttpFoundation\Request), 1) #7 /var/www/domainedescolibris/vendor/symfony/src/Symfony/Bundle/FrameworkBundle/HttpKernel.php(50): Symfony\Component\HttpKernel\HttpKernel->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true) #8 /var/www/domainedescolibris/vendor/symfony/src/Symfony/Component/HttpKernel/Kernel.php(188): Symfony\Bundle\FrameworkBundle\HttpKernel->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true) #9 /var/www/domainedescolibris/web/app.php(12): Symfony\Component\HttpKernel\Kernel->handle(Object(Symfony\Component\HttpFoundation\Request)) #10 {main} Next exception 'Symfony\Component\HttpKernel\Exception\NotFoundHttpException' with message 'No route found for "GET /sitemap.xml"' in /var/www/domainedescolibris/vendor/symfony/src/Symfony/Component/HttpKernel/EventListener/RouterListener.php:69 Stack trace: #0 [internal function]: Symfony\Component\HttpKernel\EventListener\RouterListener->onKernelRequest(Object(Symfony\Component\HttpKernel\Event\GetResponseEvent)) #1 /var/www/domainedescolibris/vendor/symfony/src/Symfony/Component/EventDispatcher/EventDispatcher.php(164): call_user_func(Array, Object(Symfony\Component\HttpKernel\Event\GetResponseEvent)) #2 /var/www/domainedescolibris/vendor/symfony/src/Symfony/Component/EventDispatcher/EventDispatcher.php(53): Symfony\Component\EventDispatcher\EventDispatcher->doDispatch(Array, 'kernel.request', Object(Symfony\Component\HttpKernel\Event\GetResponseEvent)) #3 /var/www/domainedescolibris/vendor/symfony/src/Symfony/Component/EventDispatcher/ContainerAwareEventDispatcher.php(165): Symfony\Component\EventDispatcher\EventDispatcher->dispatch('kernel.request', Object(Symfony\Component\HttpKernel\Event\GetResponseEvent)) #4 /var/www/domainedescolibris/vendor/symfony/src/Symfony/Component/HttpKernel/HttpKernel.php(109): Symfony\Component\EventDispatcher\ContainerAwareEventDispatcher->dispatch('kernel.request', Object(Symfony\Component\HttpKernel\Event\GetResponseEvent)) #5 /var/www/domainedescolibris/vendor/symfony/src/Symfony/Component/HttpKernel/HttpKernel.php(72): Symfony\Component\HttpKernel\HttpKernel->handleRaw(Object(Symfony\Component\HttpFoundation\Request), 1) #6 /var/www/domainedescolibris/vendor/symfony/src/Symfony/Bundle/FrameworkBundle/HttpKernel.php(50): Symfony\Component\HttpKernel\HttpKernel->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true) #7 /var/www/domainedescolibris/vendor/symfony/src/Symfony/Component/HttpKernel/Kernel.php(188): Symfony\Bundle\FrameworkBundle\HttpKernel->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true) #8 /var/www/domainedescolibris/web/app.php(12): Symfony\Component\HttpKernel\Kernel->handle(Object(Symfony\Component\HttpFoundation\Request)) #9 {main}