After installing SQL server 2008 or SQL server 2008 R2 and using reporting services for the first time you may encounter this error:
The report server has encountered a configuration error. (rsServerConfigurationError)
Exactly as the error message says – you have not configured reporting services correctly. In my case it was because I had not created the reporting services database from within the Reporting Services Configuration Manger tool.
Best thing to do is go through each configuration section in the tool and address any comments prefixed by an exclamations mark.