MS SQL Server Reporting Services error: The report server has encountered a configuration error

After install of the Sql Server 2005 I got the error:

The report server has encountered a configuration error. See the report server log files for more information. (rsServerConfigurationError)
Access to the path 'C:\Program Files\Microsoft SQL Server\MSSQL.3\Reporting Services\ReportServer\RSReportServer.config' is denied.

How to connect to SQL Server 2008 using 2005

While supporting the website калькулятор на автокредит I encountered a problem when I use SQL Server Management Studio in SQL Server 2005 to connect to an instance of SQL Server 2008.
To solve this problem, I installed Microsoft SQL Server 2005 Service Pack 2. After that I also installed "Cumulative update package 12 for SQL Server 2005 Service Pack 2 (server and client)".
And, voila, it works!