Quantum in Frontend

[serge-sd]

Hello
I want to access to a part of joomla/images files to some peoples.
I can use Filezilla, but I think that it is a little complex for these peoples.
It seems tha quantum may be a solution.
So I create a menu base on index.php?option=com_quantummanager&view=quantummanager.

But when I open the page in frontend, I have the error message : "JLIB_APPLICATION_ERROR_NOT_ACCESS"

Could you help me ?
BR

Serge