Probleme d'installation xibo 1.8.5 centos 6

installation problem xibo 1.8.5 centos 6

i got this message when i accessed the second install step of xibo


a solution that will be appreciated

Please go back to the manual, and in particular the section dealing with preparing your environment.

You haven’t configured URL rewriting correctly, or your webserver configuration prevents the files we ship from being honoured.