Access to the path 'C:\Program Files\Microsoft SQL Server\MSSQL.1\Reporting Services\ReportServer\RSReportServer.config' is denied

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.1\Reporting Services\ReportServer\RSReportServer.config' is denied.

Solution:

1. Right click RSReportServer.config file
2. GO to Properties
3. Click Security tab
4. Click Add button
5. Type "Network Service" and select "Location" as local PC.
6. Click "Check Names" button
7. Click OK; OK and you it should work now.