You cannot upgrade from the currently installed version of VMM to System Center 2012 R2 Virtual Machine Manager. You must ...

You cannot upgrade from the currently installed version of VMM to System Center 2012 R2 Virtual Machine Manager. You must first uninstall VMM, and then install System Center 2012 R2. If you are running System Center 2012, when you uninstall VMM, you can retain the database. When you install System Center 2012 R2, use the retained database.