Domain User Access

[teelee]

Hello All,
Has anyone had a problem with Domain users signing on to the Cognos Portal before access to reports has been given?  This is my problem...

We have AD (Active Directory), in testing sign-on to the Portal, a user was able to see all of the folders/reports/dashboards without any restrictions.  The user was even able to create reports.  And you know that if they can create reports, they can also change them, which is a big NO, NO, right.

So how can I restrict access to these reports across the Domain before I've had a chance to set restrictions?  Does the Domain user group need access no, or yes if any ???

Thanks in advance for all of your assistance :)