just an information :
if you get this classical message
The file browser is disabled for security reasons. Please contact your system administrator and check the CKFinder configuration file.
with recent versions of CKEditor - CKFinder, don't forget to check if your website, as
"Drupal automatically generates a unique session cookie name for each site based on its full domain name.
For Drupal, you have to check in administration/reports/dashboard if you have any problem with cookies.
if you do have some, go to sites/default/,
/* $cookie_domain = '.example.com';
indicate the appropriate name (don't forget the first dot),
change chmod of settings.php and default on server to 777,
upload the new file settings.php,
rechange chmod of settings.php (404) and default(505) on server,
reconnect you on your site, clear caches ... ' should work