I've just upgraded an existing SQL Server 2005 to 2008 by running the installer (not the platform installer). It all seems to have worked - there were no errors reported and my code that connects to these databases still works fine. The problem is, when I try installing SQL Server Management Studio Express 2008 I am shown then following error message when I select to add new features to an existing instance of SQL Server 2008: The SQL Server instance 'SQL1MINUS102' already has an Instance ID '2' that is different than the specified Instance ID 'SQL1MINUS102'. Specifying more than one instance ID for the same SQL Server instance is not supported. Here is a screenshot of the installation dialog and the setup discovery report: Screenshot Notice that there are two instances with the same name. So any ideas how I should recifiy this so that I can install Management studio? Thanks in advance