When launching the Reporting Web Portal a "Services Unavailable" error message occurs, and the following events are logged in the System Event log:
Event ID: 1021
The identity of application pool, "Reporting Web Portal Application Pool" is invalid.
If it remains invalid when the first request for the application pool is processed, the application pool will be disabled.
The data field contains the error number.
Event ID: 1059
A failure was encountered while launching the process serving application pool "Reporting Web Portal Application Pool".
The application pool has been disabled.