setting role permission to a folder of reports but still access denied

I have a folder REPORTS containing all reports created from adhoc views. Another folder datasources containing the datasource.

Another folder containing the adhoc reports. But I was to give access to  user "R" to see only the REPORTS folder. 

so I created role_reports and on REports folder put permission of this role to "administer", and on the "Datasources" and "Ad hoc reports" permission no access.

I then went inside datasources folder and selected the datasource and gave permission "Read-only" Same for the ad hoc reports folder, I selected the adhocs related to the reports and gave permission "Read-only"

But still after logging to user "R", I see the "Reports" folder and when I try to click on a report it opens and gives me access denied. What am i missing?