There is no Adobe Flash version available for the 64-bit Windows Vista operating system. To install the Adobe Flash Version for 64-bit Windows Vista operating system, the 32-bit Internet Explorer web browser is required. Some changes in the configuration of the Windows Vista operating system are also required. From the Macromedia Flash directory the FlashUtil9b must be run as administrator to install Adobe Flash on 64-bit Windows Vista operating system. After running FlashUtil9b, the UAC prompt will appear. The Flash Player installation Wizard has to be followed to complete the installation of the Adobe Flash.
As you know, there isn't a flash player version available for Vista 64-bit platform. So you will not be able to watch streaming videos or access some websites. If you have tried downloading Adobe Flash Player for Windows 64-bit platforms, you probably got this error message "Sorry, your platform is not supported".
You should install the 32-bit version of Internet Explorer to be used on the 64-bit operating system.