When i try to login to Nagios in my web browser and after having repeatedly enter my login and password on my Nagios page http://127.0.0.1/nagios/, i get this :

Authorization Required

This server could not verify that you are authorized to access the document requested. Either you supplied the wrong credentials (e.g., bad password), or your browser doesn't understand how to supply the credentials required. Apache/2.2.15 (Red Hat) Server at 127.0.0.1 Port 80

I changed the password :

htpasswd -c /etc/nagios/htpasswd.users nagiosadmin

And restart the server :

service httpd restart

But without result !