About Windows Installer on 64-Bit Operating Systems
Windows Installer runs as a service on computers using 32-bit or 64-bit Windows. Versions of the installer earlier than version 2.0 can install and manage 32-bit Windows Installer Packages only on 32-bit operating systems. Note that you cannot advertise or install a 64-bit application on a 32-bit operating system.
A Windows Installer package must be specified as either a 32-bit or a 64-bit package; it cannot be specified as neutral. On a computer using a 64-bit operating system, the Windows Installer service is hosted in a 64-bit process that installs both 32-bit and 64-bit packages. Windows Installer installs three types of Windows installer packages on a computer running a 64-bit operating system:
- 32-bit packages that contain only 32-bit components.
- 64-bit packages containing some 32 bit components.
- 64-bit packages containing only 64 bit components.
The follow sections describe the two types of Windows Installer packages and the new installer properties provided by Windows Installer for 64-bit packages.