Errors on Opening the reporting manger (http://localhost/reports) in R2/Win7/IE9: The report server cannot decrypt the symmetric key

Problem 1: 

I tried to open http://localshot/reportserver to examine the reports deployed earlier today. Strangely, my laptop shows the Intranet warning. I ignored it. Enter the logon ID/PW for the laptop. It complains the insufficient privilege. I open it in IE as an admin, the same problem! I switched to Reproting Services Configuration Manager to change the RS service account to local system. It showed an error. Click it for more details:

"The report server cannot decrypt the symmetric key used to access sensitive or encrypted data in a report server database. You must either restore a backup key or delete all encrypted content..."

Solution: 

I clicked the Delete button for the encrypted content.

Problem 2: 

Then I got the insufficient permission error logging as a local admin on my laptop.

Solution: 

Turn off the UAC.

Issue 3: 

When I log into http://localhost/reports, I can see site settings now. But I cannot add the local admin user (i.e., CK-PC\CK) into the content manager role in Report Manager. I only see the two system roles: Sys Admin and Sys User. I confused myself on 'Site Settings' and 'Folder Settings'. The assignment of content manager is in Folder Settings.

This post helped me

http://www.sql-server-performance.com/2011/security-ssrs-reporting-error/

Problem 4: 

Windows Security Dialog Box Pops up each time when opening http://localhost/reports in IE or Authentication Required in Chrome

Trial 1: modifying the rsreportserver.config file based on the suggestions below, does not help

http://msdn.microsoft.com/en-us/library/cc281253.aspx

Trial 2: adding http://localhost to the trusted site as suggested below, does not help

http://sqlblogcasts.com/blogs/testas/archive/2010/06/03/accessing-ssrs-report-manager-on-windows-7-and-windows-2008-server.aspx

Solution:

Adding http://localhost as a trusted intranet site works for me, no more pop up asking for login credentials.

IE|Tools|Internet Options|Security|Local Intranet|Sites|Advanced|entering http://localhost|Add