C10 sECURITY ERROR

[Cognos8]

Hi ,
I have installed c10.1. 2 webserver, 1 cm , 3 dispatcher.
I am part of admin. able to lauch the environment properly. Because i have been added in system admin. For my user i have created group and this group is mapped to  new role ex: finance_admin. This role has been added in capability and function. Also given access to public folders. But when any of my user launches cognos 0 url they are getting the error

"Unabled to authenticate .The provided credentials are restricted from accessing IBM cognos 8.Please contact admin".

iT SAYS  seccurity error.. But i am confident in cognos connection security level nothing to do. Please reply ASAP.