You need to check following:
1.User rights for the particular user ( advanced settings)
2.businessobjects Application in cmc - Infoview and apply advanced rights and check rights for Everyone group.
3.To make sure clicl Check user rights which will list the entire list of rights
4.make sure there is No Access at Everyone Group.
Check this Save Public Documents in Personal folders but deny saving...
Hope this Helps 
Disha 
(BOB member since 2007-05-23)