You don't have permission to access /mrtg/ on this server MRTG CentOS

MRTG

You don't have permission to access /mrtg/ on this server
or access denied

1.edite httpd.conf
2.find    DirectoryIndex   index.php
3.add  index.html  and save
   exp : DirectoryIndex   index.php index.html
4.service httpd restart