Images display and user rights

Hello,
When I open Dokeos with Firefox ou i.e, some images not appear becous one file is missing :
File does not exist: /var/www/html/main/css/default.css, referer: http://adresse de dokeos /user_portal.php
Could you please explain me where I could find this file for DOKEOS 1.8.6.1 ?
Thanks in advance,
Sarah MAMAN

This is typically a user
This is typically a user rights issue. Go to /var/www/dokeos (or your corresponding dokeos root) Try a #chmod 755 -R * to change permissions on all files. Then do a cd .. and do a chmod 755 dokeos
Thanks !!
Everything is OK, now !!!
Thanks a lot
Sarah