You try to install a Microsoft SQL Server 2008 Reporting Services instance by using an instance name that you previously uninstalled from the computer. When you do this, you may receive one of the following error messages:
The catalog database file exists. Select a files-only mode installation.
The catalog temporary database file exists. Select a files-only mode installation.
This issue occurs because the databases for the SQL Server 2008 Reporting Services instance that you want to install already exist on the computer.
To resolve this issue, move, rename, or delete the existing Report Server databases. Or, use a different instance name.
By default, when you install an instance of SQL Server 2008 Reporting Services, the instance setup process creates two new databases that are named "ReportServer_Instance_Name" and "ReportServer_Instance_nameTempDB." These databases are created under the following folder for the instance of the SQL Server that you are running:
Note For the default MSSQLSERVER instance, the database names are "ReportServer" and "ReportServerTempDB."
These databases may contain user data. Therefore, the Setup program does not delete these databases when you uninstall a SQL Server 2008 Reporting Services instance. When you install an instance that has the same instance name, the Setup program detects that the Report Server databases already exist for that instance name. When this occurs, you receive the error message that is mentioned in the "Symptoms" section.
"SQL Server 2008 Reporting Services" SQL2008RelNoteReportingServices