my vqadmin doesnt work

Hi every body
I installed vqmail for the first time on linux7.X   I did every thing
that was in the “install instruction”
But when I connect to it this error appears:
 
 
 
 Authentication Failed Username unknown
 
vQadmin was unable to determine your username, which
means your webserver is improperly configured to run
with this CGI.  For security reasons, this script
will not run without Apache htaccess lists.
 
Pleas could you tell me what should I do
 
Regards Bahare Abedin