Cognos Security issue

[jamsheer]

I set up the cognos security settings by refering the security administration guide.I restrict the access to only authorised users using Active Directory Service.But i am not able to restrict the users access al users in my directory service  able to do anything.So can u tell what is the possible cause for that.
My settings
1.restricted acces
2.Access only to members of the built in namspace
3.I removed the everyone group from all the  roles
4.given controller role to a user


So pleas somebody help me to fix this problem
i am not able to restrict the users .
Documents are saying about system administrators role what is it . I dont see it.

Jamsheer k